Articles by Keith Tripp

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Trap Primer: Friend or Foe?

A 1960's style floor drain with a copper trap primer tube supplying water to the trap seal.

A 1960’s style floor drain with a copper trap primer tube

supplying water to the trap seal.

Trap Primer: Friend or Foe?

by Keith Tripp. Revised May, 2023

In Canada we have some of the best and cheapest water supplies anywhere in the world. This means wastage of water does not get much attention. However, water costs are increasing dramatically and frequently. In this article, I explain a plumbing system that can be the source of huge water wastage.

Officially called a trap seal primer, the purpose of this system is to maintain water level in the trap seal at the floor drain in the basement or any other drain that is not connected to a fixture. From here on in I‘ll just call it a primer.  The most common primers are serving floor drains in the basement. The purpose of the trap seal is to create a barrier between the house air that we breath, and the nasty air of the sewer pipes on the other side of the trap. Sewer gasses are hazardous to human health and since the early days of plumbing, trap seals have been employed in the drain systems to prevent exposure to sewer gasses. Failure of primer systems can result in sewer gasses entering the house, or in extreme waste of water.

All fixtures such as sinks and baths have traps installed in the drain just below the fixture. These traps receive water each time the fixture drain is used, so they are not at risk of drying out as long as the fixture is used at least once in a while. Toilets have built in traps so there is no trap installed in the drain pipe from a toilet. The water you see in the toilet bowl is acting as the trap seal. Floor drains do not receive water on a regular basis, so they are at risk of drying out. hence the requirement for the trap primer.

A traditional style laundry faucet with primer tube attached to the faucet body.

A traditional style laundry faucet with primer tube attached to the faucet body.

The most common water source for the primer system is the laundry tub faucet. At the underside of the traditional laundry faucet body is a fitting to which a tube can be attached.  See photo. Whenever the valves, hot or cold, are opened, water flowing in the body of the faucet runs through the primer tube. On older houses (60s and 70s) the tube was copper and is routed  through the cement floor slab and enters the floor drain pipe through the side of the vertical drain, just above the trap seal water level.  On newer houses, the tube is plastic and is routed through a larger plastic conduit that runs through the concrete floor slab to the drain. If there are multiple floor drains the tubes may be split to flow to all the floor drains. This type of direct flow primer system has been installed in original construction since about the early 1960s.


What can go wrong? Too much water! The only thing worse than a primer that doesn’t work is one that works all the time!  Failure of primer systems can result in a continuous flow of water to the drain, often going undetected. This can be hot water, which means energy as well as water are wasted. Worn washers or washer seats, or a partly open valve at the laundry faucet can result in water flowing continuously through the primer tube, often without detection. If water is leaking past the washers in the faucet, it will take the path of least resistance. Based on location, that path is the trap primer tube connected to the underside of the faucet body. The leakage can occur through either the hot or the cold side or both. The faucet won’t drip, so this condition will often go undetected. Sometimes a slight gurgling noise can be heard, as air is drawn in to the faucet to replace water that escapes through the faucet body to the floor drain. If hot water is leaking through, over time the concrete floor slab may get warmed up by this. Substantial amounts of water can be lost this way resulting in HUGE water bills and water heating bills.

What can go wrong? Not enough water! If the primer fails to provide water to the trap, the trap seal water in the drain may evaporate, resulting in an open trap and sewer gasses will enter the house. This is most common at drains supplied from a split tube where the flow really is not adequate to service more than one floor drain. Tubing or conduit could be damaged or poorly routed and preventing flow of the water to the trap. Strangely enough, the dried-out trap does not always emit an offensive odour to warn of what has happened. The extent of odour depends on where the drain is located relative to the rest of the sewer drains, and air flow through the house. I have however, walked in to cold rooms with dried out drain traps where the odour could knock you off your feet. This is relatively common in new construction where builders have failed to commission the primer system.  (note: not all cold rooms have floor drains.)

To test the primer, simply operate the fixture it is attached to, such as running the laundry tub water, and water should be visible or audible flowing in to the floor drain just below floor level and above the trap seal water.

The white tube is a primer tube, split to serve two floor drains.

The white tube is a primer tube, split to serve two floor drains.

If there is no laundry tub, or if the laundry faucet is not a traditional laundry faucet then it is important to confirm presence of a trap primer system. Sometimes its hard to find them. In a new house, ask the builder to identify the primer location if you can’t find it. Primer tubes of the direct flow type described above can also be connected to toilet flush systems, and to shower-head supply pipes.  The shower connections are becoming more popular as fewer standard type laundry faucets are being installed in new construction. There is potential for excessive water flow from the shower connections and that will include waste of hot water.

There are primer devices that are actuated by a pressure drop. These are used when a traditional laundry faucet is not available at a reasonable distance from the drain. They can be installed on any water line and will direct a flow of water to the drain when pressure drops because of water usage on that line. Valves connected to timers can also be sued as a primer system.


There are primer substitute devices that don’t require water flow. These are sometimes used in laundry room floor drains in new construction. Look down the drain. If the opening is blocked with a rubber diaphragm this is probably a trap sealing device. Don’t confuse this with a device that may be installed in a basement floor drain to prevent backflow.

If the primer doesn’t work, repair accordingly. In the short term, pour a few buckets of water down the drain every month or so to maintain water level in the trap.

Related Tips

Baby clothes washers? Recently I came across clients who had installed “baby clothes” washers in their laundry rooms. These are small washing machines that require the water hose to be connected to a faucet. The washing machine has a solenoid valve that controls flow of water in to the machine, so it is not necessary to shut off the water at the faucet.  The washer supply hoses were attached to the threaded laundry faucet spout, and the laundry faucet taps were in the open position. With this arrangement water was flowing full time through the primer tube to the floor drain even though no water was flowing to the washing machine.

Installing a new laundry faucet? Only the basic laundry tub faucets have the primer connection. If installing a kitchen style faucet at a laundry sink, a different primer system will be required.

Leaving a house vacant for more than a few weeks? A primer is only effective if water is run on the pipes or faucet that will trigger the primer action.  If a house is vacant, no primer water will be flowing. If a house is vacant, or a laundry faucet it not regularly used, then it’s a good idea to run water every few weeks for all fixtures including those that do not have primers.

Questions about trap primers or home inspections? Email to Keith Tripp ,


How to use NUANS name search for free.

by Keith Tripp, revised January 2021

I often get asked to refer companies for house repairs. I don’t give referrals, however I may provide some tips on how to select a company to work with. One of those tips is to check that a company really exists under the name they are providing. One resource for doing that is the NUANS database. This is a Government of Canada service that can be accessed for free in the early stages of the name selection process.

Years ago I wrote about the NUANS business name search data base and how to use it for free to check if a business really exists. At that time a password was required, and the password expired every few months. In early 2020 I went back to the NUANS site and found that a password is no longer required. There are some recent changes to the website, so the updates provided here are based on January 2021.

NUANS is one of a few simple tests I apply when selecting a vendor. As an example, a guy had knocked at my door looking for work trimming trees, and he left me his business card. He seemed like a credible hard-working dude, so I decided to check if his company really existed under the name on the card. I will not use the real company name of the tree trimmer, but the real name was along the lines of   A Right Proper Job Tree Service.  

I apply three simple tests. His business card passed my first test, which is that he had both his first and last name on it. What’s with these driveway paving company sales reps who all only have one name like Madonna? If the card says call Joe, it’s headed straight to the garbage can. He passed my second test also, because there was a local address on the business card. I always recommend going with local providers when feasible. If things go sour when you hire someone, will you be able to identify them, track them down and follow up to sue them or otherwise recover your losses?

The third test is whether the business really exists as a legal entity. Many business names floating around are not the real business name, and if you can’t connect a business with the legal entity then you may be out of luck for follow up.  This is where the NUANS site comes in. NUANS is a service intended mostly for selecting business names for establishing a new business. The NUANS site is entitled Nuans-Corporate name and trademark search, but don’t let that fool you. All types of business names are on the register, including sole proprietorships. The purpose of the site is to avoid conflicting or duplicating names when a business is established, however it has, with a few exceptions, all of the company names in Canada. If the company name is not on NUANS, then a red flag should be raised.

The legal people tell me that there is still risk that a company is not in good standing, even with their status showing as “Active” on NUANS. So finding the name on NUANS is a good start, but not the end-all, and not finding the name is a definite red flag.

Here are the steps for finding a company name on NUANS.

No password is required, and Keith’s tips will show you how to use it for free. That’s a $13.80 per report savings.

Go to Check that you are at the government site and not a third party copycat site. There is a Government of Canada emblem at the top of the page, and the first page has a banner for: Innovation, Science and Economic Development Canada, and a button to select language of choice. If you google search for nuans, there is a good chance of ending up at a third party provider’s site.

After selecting language, the next page will be headed: Nuans-Corporate name and trademark reports.

SCROLL DOWN to the button : ORDER A NUANS REPORT Above this button, it indicates a $13.80 charge, but you won’t be paying that unless you choose to go thru all five steps.

Press the button and it takes you to Step 1 0f 5: Propose a Corporate name

Towards the bottom of the page is a blank box: “Enter proposed name of corporation”

Type in the name in the blank box that you are searching. For example,   PROVANTAGE PROPERTY INSPECTION

A screen will pop up with Exact match warning…. This is what you will see for companies that exist.

And you will see both my provincial and federal corporate listings, with status: ACTIVE:


Rank Name Jurisdiction and number Creation date (YYYY-MM-DD) Status Business activity
1 ProVantage Property Inspection Inc. CD-6728481 2007-02-28 Active  
2 PROVANTAGE PROPERTY INSPECTION INC. ON-3025560 2007-02-28 Active  

Now try with a shorter version. Click on Enter another name: and enter just the key word PROVANTAGE

Again, an EXACT match warning will pop up, and a table listing all the company containing PROVANTAGE will appear. I will show part of it here:

Rank Name Jurisdiction and number Creation date (YYYY-MM-DD) Status Business activity
1 PROVANTAGE TM-1761252 2015-12-24 Active 16
2 PROVANTAGE TM-0702790 1992-04-10 Inactive 35 , 37
3 PROVANTAGE TM-1263740 2005-07-06 Inactive 1 , 4
4 PROVANTAGE TM-1588830 2012-08-03 Active 42 , 44
5 PROVANTAGE TM-1563001 2012-02-07 Active 1 , 16
6 PROVANTAGE BUSINESS CONSULTING INC. ON-2595628 2017-09-07 Active  
7 ProVantage Property Inspection Inc. CD-6728481 2007-02-28 Active  
8 PROVANTAGE HOME SERVICES ON-210387569 2011-04-07 Active  
9 PROVANTAGE HOME INSPECTION ON-191145242 2009-11-12 Active  
10 PROVANTAGE TRADING INC. ON-1095714 1994-09-07 Active  


If no exact match warning comes up, use the shorter word versions to check for similar names. You can enter many names and search for free.  If the name is not on this NUANS list, then either they don’t exist, or the company may not be registered, or is not officially operating under the name provided. If you want to do business with that company, go back to them and ask for the real company name, and confirm it on NUANS. You may find the company is operating as a numbered company, in which case you want those details from them.

Have fun with it, and Buyer Beware!

House Shopping 101: Where to find house info. in 2023.

Revised 2023

By Keith Tripp    Text to 416 320 8863 email

To prepare quotes and to prepare for inspections, the more I know about the house, the better. Today you can have almost as much info as the real estate salespeople, and at no cost. You should have this same level of info when house shopping and doing your own research.

Age Counts! :For a home inspector, age of the house is extremely important. The age will determine risks related to older electrical and plumbing components, energy performance, and foundation (basement) leakage risk. The true age of the house is often not highlighted in the selling material. Some physical age indicators include: street date (on the sewer caps), installation tags inside the house, window manufacture dates, HVAC equipment dates, type of construction, construction materials used and location. Always find out the year of construction of the OLDEST part of the house when house shopping.

Here are some of the (FREE!!!)  tools I use to get info on the property here in the Greater Toronto Area, Ontario, Canada.

HOUSESIGMA.COM : Now my “go-to” site. It is the first site I open up when I have an address to work with, and it also has a map search function that shows not only active listings, but recent activity in the area. It has bigger and better photos than There is also an alert system that will email you when status of a listing changes. This is one of the “new kids on the block”, arriving when laws were changed to allow for access to the MLS info. This is a powerful tool that real estate salespeople wish did not exist. These new sites are constantly under the scrutiny of the powerful real estate lobby group. Prior to HouseSigma I was using Bungol was shut down in August 2020.

HouseSigma has all of the info from except not the name of listing agent. It does have the listing# in the Key Facts section, so that can be used to quickly find the listing in, where the listing brokerage and salesperson name will be provided.  The big plus is it shows previous listing history such as terminations, price changes, and previous sales. It shows listing date and time on the market. It also shows when a conditional offer is in place and the expiry date of that condition. Age is shown but the range is quite broad. There is also an indicator of market conditions for each house, ranging from Buyer’s Market to Balanced to Seller’s market , and an estimated selling price. This is the public version of the MLS info. It does not show all the info the real estate salespeople can see, for example names of owners and age of house. Search by address on the map, or by listing number: shows house description and names of listing agent. It has recently added Annual Property Taxes. This is probably the best site for cruising neighbourhoods. When reading the listings, keep in mind they are sales pitches with all the positives, but rarely mention any of the negatives of the property. All real estate salespeople in the Ontario system are paid by the sellers, whether they class themselves as the listing agent or the “buying” agent.

Google maps: Photos over previous years can show dates of exterior renovations and even date of construction for newer homes. Click on Street View and the option to look at photo view going back over the years. I can often determine the approximate date that a roof was redone, or significant changes to exterior cladding by looking at this feature. Also good to look at proximity to highways, bodies of water, railroad tracks, industrial areas. Using satellite view shows green spaces and can give a sense of water flow through the area. Satellite view can even show some roof details such as vents and skylights. MPAC is the Municipal Property Assessment Corporation. This organization does the property assessments to determine property taxes. You can sign on by using the tax roll number of your existing property. Unfortunately, without a tax roll number I believe you can’t access this info. Once registered, you can go straight to Use the “About My Property: Browse My Neighbourhood” function to search the map. This is the best place to confirm year built. Also shows: Square Feet, Lot size, Number of storeys, Current Value Assessed, Sales Indicator (date of previous sales only back to 2012, not amount). A note of caution on year built on MPAC: If a house underwent significant renovation or rebuild, MPAC may only indicate the date of the newer work. I have inspected homes that were listed as new on MPAC, only to find old foundations and floor structures left in place.


Keith Tripp is a professional home inspector in Toronto, Ontario, Canada

Where Drizzy’s Drizzle gonna go? And other mansard roof raps.

By Keith Tripp, 2020  Text to 416-320-8863



This new build on Park Lane Circle in Toronto’s (does anyone call it the Six ?) prestigious Bridle Path area is, according to multiple media reports, the property of Toronto recording artist Drake, Aubrey Drake Graham aka Drizzy.

This style of roof is called mansard. This mansard roof style is increasingly popular on new infill mansions. Height restrictions, and the demand for interior ceiling heights of 10 feet and up are probably contributors to the popularity of the mansard. It is a way of disguising an otherwise unattractive flat roof.

At this Park Lane Circle home, based on photos available on the internet, there is a flat roof hidden by the mansard sides. This mansard roof is finished with a combination of shingles and metal roofing material. The metal has a nice pewter look. The sides project vertically above the flat roof level. The mansard sides offer protection from view for substantially sized HVAC equipment installed on the flat roof. The mansard roof is doing double duty as functional cladding and a false front for aesthetics. The attic space behind the sides is presumably about half way up the walls. The portholes through the mansard sides (a wee bit on the ugly side do you agree?) most likely are for ventilation of that attic space. These are my assumptions based on viewing the property from the road and looking at photos on-line.

drizzy4What’s unique about this house is that the roof is offset to the inside of the exterior cladding. There is effectively a ledge on top of the exterior cladding. Note the snow sitting on this ledge. There is no visible gutter system, and you have to look very closely to see a downspout. Because there is no roof overhang to provide air flow for attic venting, the large portholes will be providing cross-flow venting through the attic space. With this roof, most of the roof water will be collected at the flat roof and disposed of through a drain system that may be built in to the walls of the house. Some water will be captured by the mansard sides and will require management. I suspect there is a gutter trough neatly concealed at the base of that mansard roof, behind the masonry units, and downspouts are either concealed or are at the sides of the house. The porthole style vents on this house are not a common thing. They look nice and large, however the screens will have to be kept clean. The porthole design also provides harbourage for birds, who will no doubt be tempted to nest at the base of the circle, or on the top protrusion. Even with the gutter system, I suspect the snow melt and rain water will have some tendency to flow down the exterior cladding, unless there is a good drip edge (capillary break). Protrusions in the cladding may catch the water as it falls. I will have to check out the performance on a wet day to see how it’s doing. If water runs down the cladding, it will cause staining, and eventually deterioration of the cladding and mortar.

drizzy5This is a more traditional mansard roof. The flat roof is above the mansard sides, and vents and HVAC equipment are visible on the roof. Water is running down from the flat roof, and is captured in gutters at the bottom of the mansard sides. The sides project slightly beyond the exterior cladding, and are probably vented to allow some air flow in to the attic space.




drizzy6This is another mansard style roof house under construction, just down the road from Drake’s place. This is the more common approach where a flat or almost flat top roof where water from the top flat or almost flat roof will drain down the sides of the mansard. This roof has a generous overhang that is good for ventilation and for protecting the exterior cladding from water.




drizzy7There is good reason to worry about where your drizzle goes. See this relatively new building with a mansard style roof. Fancy architectural features at the front of the house combined with poor management of water flow have led to significant premature brick deterioration.




drizzy 8The decision to create a complicated roof line with a small section not served by a gutter to accommodate some fake foam balusters has backfired. Staining down the finish shows that water likes to flow downhill unless told otherwise. The brick in the area of flow is already significantly damaged from freeze-thaw action, with spalling occurring even a dozen rows down the wall and significant mortar loss at the units above the window opening. The situation is exacerbated because this area of roof is receiving water from the gable roof above. Some costly brick repairs will soon be required.

I have never understood any benefits of the mansard design. I regard it as an unfortunate design that results from height restrictions. On older installations (60s and 70s) there is high risk of leakage and subsequent rot occurring around window openings. The roof tops are more difficult to access because ladders can’t be placed at a suitable angle to traverse the mansard sides and reach the top. Smart design would include an access hatch to the roof, but most houses I inspect do not have a roof hatch. Roof inspection or repair requires professional crews with lifts and cranes or extra long ladders.

It remains to be seen how the Drizzy mansion will perform. The front has a South-West exposure that will be relatively dry, however the rear of the building with the North-East exposure is going to be subject to direct rain impingement , and will be slower to dry out. This is where I would expect to see water staining occurring on the masonry within a few years. Maybe one day someone will call me on my cell phone to check it out!

“Don’t worry, the City inspected it.” #8: What’s in YOUR attic? Comfort or Con?

by Keith Tripp, 2020

phone or text: 416-320-8863

con3This is the eighth in a series on construction defects found in the Greater Toronto Area, Ontario, Canada. Two issues are described: 1) Fraudulent substitution of materials 2) Underfill of volume of materials, which could also be considered as fraud.

This photo shows insulation materials in an attic. To the untrained eye, there may be nothing amiss. Those working in the insulation business and attic sleuths like myself however can see that there are two different materials present. The darker material is cellulose, with a typical R value of 3.8 per inch. The white material is fiberglass which provides about R value of about 2.8 per inch.





con2In the undisturbed state, a thin layer of cellulose covers the underlying fiberglass as seen at the photo to the left.







con1A little digging below the surface reveals the underlying fiberglass as seen to the left.

If finding this in an older house, there would be no cause for alarm as often newer materials get layered on top of existing old insulation materials. However, these photos are all taken on warranty inspections on new construction in Oakville, Ontario, Canada, so it is not acceptable. I consider claiming to use one material, substituting a cheaper, lesser material, and covering it with a thin layer of the correct material to be fraud. The installer is aware that the chances of the insulation being inspected at close range are quite low. Attics are difficult and unpleasant places to get in to. The builder does not do a detailed inspection, the City inspector does not go in the attic, and the average homeowner will never know what is overhead. The loser in the end is the unwitting homeowner who has not received what they paid for and will pay the price in heating and cooling bills and possible discomfort in the years to come.

The ceiling insulation requirement on new construction in the GTA is R50 or R60 depending on which menu of SB12 energy compliance package the builder chose to use to meet basic code. A label at the entrance to the attic will display the material used, claimed R value, and the required depth to provide the R value. Often the installing company’s name is on the label.

Let’s use R60 as an example to see the impact of the substituted material.

Depth of Cellulose required for R60 is 16.1 inches.

Depth of fiberglass required for R60 is about 21.5 inches.

If claiming to use cellulose, and really using mostly fiberglass:

16.1 inches of fiberglass= R45= 75% of claimed value. That is assuming that the full depth is installed. It is common to find the depth of insulation to be underfilled in new construction. Based on checking insulation in hundreds of attics, I find that installing  about 2/3 of the claimed amount reflects common practice. It seems this is not a new practice either, and it’s what I expect to find in attics constructed within the last 30 years or so.  The dilution of materials when combined with a typical under-fill, ( note in the photos above the total depth being only about 10-12 inches or less vs. a 16 inch requirement for example), often being about 2/3 of the claimed fill at the front part of the attic, will reduce the actual R value to 2/3 times 45 =R30. That is the sort of insulation value that we had in ceilings more than 30 years ago. So much for “Green” building eh!

con4In one of the same attics where I recently found substituted material, there was also extreme under-fill. The flashlight at left is standing on the drywall ceiling above the front of a bedroom. Depth of insulation is about 1 inch or less vs. the 16.1 inch requirement. They do say sleeping in the cold is good for you right?

Don’t hesitate to have new or nearly-new homes inspected by a professional to check for insulation underfill or substitution of materials.

It’s a common sounding from builders and the selling parties on new or almost new homes. “Don’t worry, the City inspected it”. As an inspector serving the buying community, I am often amused by that statement. My income on new and nearly new home inspections relies directly on identifying the leftover issues after all the builder and municipal inspections are complete and the first owner has taken possession. These issues don’t go away on their own, and I also find “builder issues” on resale homes, even up to 50 years after original construction.

Keith Tripp lives, works and plays in Toronto, Ontario, Canada.

Age Counts

by Keith Tripp, 2020

This is the oldest house in Scarborough, Ontario, Canada. It is the Osterhout log cabin located on the grounds of Guild Inn, surrounded by interesting architectural fragments saved from demolition by the Clark family in the 1960s and 1970s.

Age is everything when it comes to home inspection. Often the age of older renovated houses is disguised in advertising material, and even MPAC may not indicate the true age of the oldest parts of the house, such as original foundations that were left in place.guildcom1 guildcom2 guildcom3

Old foundations may be left in place intentionally so a significant rework of a house is classed as a renovation rather than a new build, and the builder may avoid requirements for Tarion warranty coverage.

When I inspect heavily renovated houses, or houses with multiple additions built in older areas, I am on a mission to find the oldest components because these represent the highest risk to the buyer. That could be foundation and structure, HVAC ductwork, and old electrical and plumbing components.

Some indicators of house or component age are: dates printed in thermopane windows, “street date” as found on sewer drain caps, date on insulation installation tag, dates on HVAC and gas line tags, dates printed on electrical wiring, dates printed on plywood and other wood panel materials, construction materials and techniques.

It is critical to determine house age. Otherwise the only thing you will know for certain is that the house is newer than the Osterhout log cabin.

Sump Systems and perforated basins.

perforatedPerforated sump basins used for a standard foundation drainage system are the wrong tool for the job, yet are common in new construction in the Toronto, Ontario, Canada area. They are full of holes (no surprise!) so water entering the basin will escape to surrounding soil under the slab, until it is fully saturated. When I test these basins by pouring water in, it will often escape and not activate the pump. The pump will only activate if the surrounding soil or other materials acts as a well and allow the water to rise.

The codes (OBC) and common sense say that storm water may discharge to a sump or drywell or to “daylight” ( outside to a drainage ditch) but NOT to the underside of the slab.  The codes do not specify what type of basin is to be used, and unfortunately City building officials accept the perforated basins.  This doesn’t make it right. Rather it shows weakness in their understanding of the requirement and interpretation of the code.

Ontario Building Code 9.14.5.  Drainage Disposal:  Drainage Disposal (1)  Foundation drains shall drain to a sewer, drainage ditch or dry well.  Sump Pits (1)  Where gravity drainage is not practical, a covered sump with an automatic pump shall be installed to discharge the water into a sewer, drainage ditch or dry well. NOT UNDER THE SLAB

Collecting all the water from the perimeter of the foundation drainage, and discharging it all under the basement slab close to the footings just is not a good idea. There is a code statement that could apply to this:

Ontario Building Code Section 9.16.  Floors-on-Ground: 9.16.3.  Drainage:  Control of Water Ingress (1)  Except as provided in Article or where it can be shown to be unnecessary, ingress of water underneath a floor-on-ground shall be prevented by grading or drainage.

A solid basin is the right tool for standard foundation drainage systems. The perforated basins are intended for collection from problem soil areas, and would typically be installed in a central location, surrounded by granular fill that facilitates water flow towards the basin.  The perforated basin may also act as a well and collect water from deeper than necessary. Most basins are about 24 inches deep. Digging a 24 inch hole under the house is likely to attract water from the surrounding soil, and this can result in significant and unwarranted water collection.

To collect or convey? Poking holes in the use of Perforated Pipe


A perforated, corrugated drain pipe.

by Keith Tripp, 2020

Sump systems used to be associated with rural properties or older house. Sumps are now, for about the last 15 years or so, making a comeback in new construction. They are installed in new subdivisions where the City does not want to assume the risk of damage to houses caused by storm system backups, and on new construction in areas with older infrastructure, where the height of the house foundation drainage system may not match the existing City storm water system.

Staring down the barrel of this sump infeed pipe, a few things become evident:
a) this is a perforated pipe with slots cut around the circumference.
b) there is no top or bottom to the pipe, it is installed with random orientation
c) the pipe looks quite clean, there has not been much water flow through the pipe

Add in a dash of common sense: a pipe full of holes will lose water unless it is submerged in water.
Conclusion: this is the wrong pipe to use as a sump infeed.

This pipe is deigned to collect water from the surface of saturated and compressed soil . This is the type of pipe commonly used here in the Toronto, Ontario, Canada region for foundation drainage around the perimeter of the footings. As per OBC (Ontario Building Code) they are OK as COLLECTION pipes to be installed alongside the footings, with the top of the pipe being below the level of the underside of the basement floor slab, and must be installed on undisturbed or compressed soil (not on gravel) and installed level, not sloped. In this application, the pipe will collect water that rises above the level of the saturated soil. Rising water will enter the pipe through the slots, then seek the path of least resistance, which will cause it to flow through the pipe until an escape route is reached. That escape route may be out through the slots in areas where the soil is not saturated or where there is no water above the soil surface, or it may be the ends of the pipe where it terminates at the sump basin, or flows in to a City storm system, or to “daylight” if the house is built on a hillside. So in theory, ( the theory being the assumption that the pipes are installed level and on compressed soil), the pipe is moving water from wet areas to dry areas, until all areas are wet and then flow out of the pipe will occur. This may explain why some some sump basins are always dry, the pipe may just be moving water from the wet side of the house, to the dry side of the house where it dissipates in the soil.

If the pipe is installed on gravel. It will only collect water that rises above the gravel, and it will quickly lose water back on to the gravel. Pipes installed on gravel or  are basically useless.

To pass from the exterior to the interior where the sump basin is installed,  pipes will pass through a sleeve in the footing.  Water will be lost at this sleeve if a perforated pipe is used. At the areas around the sump basin, there is often gravel, and the soil has been disturbed by the digging and installation of the basin. A perforated pipe will lose water as it approaches the basin. This can be a considerable volume of water, as it has been collected from the full perimeter of the house. This water may cause erosion damage, or weaken soil by ongoing cycles of saturation and drying.  Sump basins are typically installed just inside the basement wall, where they are close to the structural footings. Long term soil weakening around or under the footings is undesirable, and may result in movement of the structure.

The pipes passing through or under the footing and under the basement slab to the sump basin should be solid pipes (not perforated) that CONVEY water without losing it along the way.  These are the pipes that connect the foundation drainage pipe (a.k.a. weeping ) tile, to the sump basin which acts as a collector. From the sump basin, the water will be pumped to the exterior.

Cold Room Conversions

cold roomby Keith Tripp, 2020


A client recently asked about converting their cold room space to use as conditioned storage space or a wine cellar. Cold rooms are typically located underneath the front entrance porch and stairs. The walking porch surface is the concrete ceiling of the cold room. The sides of the cold room are poured concrete , similar to the main foundation walls. Brick is sometimes installed on the sides of the cold room walls above ground, but this is installed as decoration and is not required to be a draining veneer wall.



Here are some of the some considerations for converting a cold room here in the Greater Toronto Area, Ontario, Canada.

  • Cold rooms were not built as living space, and are often subject to water leakage especially under entrance stairways where there will be melting snow in the winter
  • Cold rooms are uninsulated, so require the addition of insulation and vapour barrier and possibly an air barrier if being used as heated space or even a cool space.
  • Cold rooms are not built to meet an air barrier standard. To the contrary, they are vented to the exterior. Even though concrete makes a good air barrier, an air barrier may be required to compensate for openings at joints.
  • The walls and ceiling of cold rooms are solid concrete, without a vented cladding wall. They are likely to be subject to inward solar driven vapour diffusion. This means vapour barrier selection is important. This would be a good application for a “smart” vapour barrier.
  • Cold rooms are vented to the exterior, so if being converted to heated space they require air flow to be connected (so installation of ductwork) and blockage of the venting to the exterior.
  • Proper wine storage requires temperature control and usually the installation of a refrigeration unit


Reduce rip-off risk: Do a really good home inspection on your existing home.

Home inspections are not just for buyers or sellers. Having a professional inspection of your existing home can reap benefits for years to come.

I recently did an inspection where the sellers were providing an inspection report from 4 years ago. This report was one of those useless checklist types in a small binder. It contained many pictures of theoretical conditions that did not apply to the house in question. I flipped through it, and struggled to find any issues identified with the house. I thought that type of report had disappeared long ago, but I guess they are still out there. This is the type of inspection and report that has given the industry a bad reputation over the years, and contributed to the call for licensing of the profession. It was a reminder that the report I have developed over the last 13 years is probably one of the best available in the home inspection market. As an aside, if you are a home buyer, keep in mind a 4 year-old home inspection is too old to be relied upon. A lot can happen in 4 years. At this house, a foundation crack had opened up considerably since a parging coat had been applied. That parging was fresh when the last inspection was done, and the foundation cracks would have been concealed.

The ProVantage report is written in an Issue-Action-Risk format. What I saw- the recommendations-risks of inaction. It is written in full sentences that make sense, not cryptic jargon. Each issue (defect) is assigned a priority of 1,2 or 3, with 1 being the highest. The report comes in two parts. Firstly, the full electronic report with defect photos, issues and description of the house. Secondly a word document list of issues in table format. The table can be sorted or cut and pasted as required. This table becomes the to-do list.

Consider a home inspection on the home you already own, for the following benefits:

1)     Separate the important issues: Often homeowners are stressed about issues that may not be that important

2)     Reduce risk of contractor rip-off. Knowing priorities and risks means you can make smarter purchasing decisions.

3)     Develop a to-do list and rough budget for the upcoming years.

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