PWF Question - Should I Stay or Should I Run?

[Andrew_Huculak]

My wife and I are thinking of buying an 1880 sq ft. home in Regina, Saskatchewan, Canada, originally built and owned by a professional engineer… it has a 9’ height in the basement that’s a PWF with a concrete floor that likely floats on the gravel base.

My parents owned a house in Maple Creek that had a PWF foundation, built around the same time… it had a wood floor. It was holding up well when they sold it a few years ago. To be fair, their soil there in sandier than in Regina.

Unusually, the concrete floor in this Regina house is in remarkably good shape for the clay soil here in Regina, and the walls are plumb. The walls are 2" X 8" PWF studs on 12" centres with blocking on each stud between the floor joists and the parallel exterior walls joists every 12". Seems to be well built. As I mentioned, they are 9" high interior basement walls!

Heating bills, (natural gas) for all of 2015 added to under $800.00, nearly half of what I pay in my current similarly sized home.

I did notice some inward deflection, (maybe 1/2") in the drywall over the studs under each of the 2 small basement windows. There’s only 2 in the entire basement. There’s likely not a strong enough plate on the bottom of the window framing on these 2 windows or enough nails to keep the pressure from pushing the studs in a bit. Or maybe they didn’t use stainless nails and they have failed. Or now that I think about it, I wonder if they used the required joist hangers on the studs under the windows. The house was built in 1983.

There is a small square pit in one corner of the basement with what looks like 2 weeping tiles coming into it from opposite directions. A small sort of large ping pong ball valve resides in the bottom of this pit. Perhaps a backwater valve of some sort? There was a bit of dampness in the bottom of this pit, but nothing significant.

What should I look for, and what should the local home inspector concentrate on? The exterior has positive slope away from the house, nice long extensions on the down spouts, the protection board at/above/below grade to protect the plastic wall membrane is there… all appears to be in good shape.

Thoughts on this major life investment would be really appreciated!

[mlarson (Michael Larson, WI Lic. # 1672-106)]

The key to the longevity of a PWF is water management.

Too many variables to give you a list here.

I have see PWF that are good and bad.

[wwilson3 (Wayne Wilson, TN 439)]

Here is some information , I would try to get all the information you can on the home and the land surrounding the home
https://www.apega.ca/assets/PDFs/foundations.pd

[rcooke (Roy D. Cooke, Sr)]

Knowing little about your area I would think a call to a couple of local Home Inspectors could be a great idea .

Even better would be to hire one of them.

[mgratton (Marcel Gratton, CMI)]

Attached are some info on PWF. You should contact a local interNACHI inspector.

[linkster (Leonard Inkster, CMI)]

Responses inline

@Andrew_Huculak

My wife and I are thinking of buying an 1880 sq ft. home in Regina, Saskatchewan, Canada, originally built and owned by a professional engineer… it has a 9’ height in the basement that’s a PWF with a concrete floor that likely floats on the gravel base. What you appear to be describing is the typical slab construction with PWF foundation walls. Without penetrating the slab, it would be impossible to determine if the slab was indeed sitting on gravel, or crushed rock, and whether it had a polythene film below the slab and UNDER the PWF footing plate. Try to identify if a screed board has been fitted to the interior at the footing plate and wall plate level, (vertical PWF board mounted vertically, and exposed at the top of the slab at the slab/wall junction)

My parents owned a house in Maple Creek that had a PWF foundation, built around the same time… it had a wood floor. It was holding up well when they sold it a few years ago. To be fair, their soil there in sandier than in Regina.

Unusually, the concrete floor in this Regina house is in remarkably good shape for the clay soil here in Regina, and the walls are plumb. The walls are 2" X 8" PWF studs on 12" centres with blocking on each stud between the floor joists and the parallel exterior walls joists every 12". Seems to be well built. As I mentioned, they are 9" high interior basement walls! Only an engineer will be able to tell you if the structural integrity of the walls design you describe are adequate for the lateral pressure of the surrounding soil. As an engineer built the home, ask for the original engineering drawings. These may be of help in the future.

Heating bills, (natural gas) for all of 2015 added to under $800.00, nearly half of what I pay in my current similarly sized home. PWF and especially Structural Insulated Panels are more thermal efficient than Concrete foundations, and it is likely this helps with the heating/cooling costs.

I did notice some inward deflection, (maybe 1/2") in the drywall over the studs under each of the 2 small basement windows. There’s only 2 in the entire basement. There’s likely not a strong enough plate on the bottom of the window framing on these 2 windows or enough nails to keep the pressure from pushing the studs in a bit. Or maybe they didn’t use stainless nails and they have failed. Or now that I think about it, I wonder if they used the required joist hangers on the studs under the windows. The house was built in 1983. Removing the drywall and inspection the structure behind is the only way to confirm a failure of the fixings or worse.

There is a small square pit in one corner of the basement with what looks like 2 weeping tiles coming into it from opposite directions. A small sort of large ping pong ball valve resides in the bottom of this pit. Perhaps a backwater valve of some sort? There was a bit of dampness in the bottom of this pit, but nothing significant. This sounds, from your explanation, as though it is a sump pit. I would expect to see a pump and ejector pipe to empty the pit if a backup occurs. Photos would be helpful to identify better…

What should I look for, and what should the local home inspector concentrate on? The exterior has positive slope away from the house, nice long extensions on the down spouts, the protection board at/above/below grade to protect the plastic wall membrane is there… all appears to be in good shape. A professional home inspector should not concentrate on any one thing, they should be looking at the home as a system. This is why a properly qualified Home Inspector is much better than a number of different trades. While the trades may all be specialists in their own field of expertise, they are frequently unaware of the effect their systems have on the other parts of the home. While a home inspector doesn’t have the deep expertise of each of the trades, they are trained in identifying when there is a concern with a component and are trained in fault diagnosis to ascertain what may be the fundamental cause of the concern and which expert trade to call in to inspect further and fix.

Thoughts on this major life investment would be really appreciated!

I hope this helps, you local InterNACHI inspector can be found here.

[plesieur (Paul Lesieur, CMI)]

I inspected a home today with a permanent wood foundation. Nice and clean and it got my blessing (so to speak.)
I built a dome home 30 years ago with a wood foundation and I heard its still dry.

[linkster (Leonard Inkster, CMI)]

@plesieur

I inspected a home today with a permanent wood foundation. Nice and clean and it got my blessing (so to speak.)
I built a dome home 30 years ago with a wood foundation and I heard its still dry.

Confusion reigns.

PWF = Pressure Treated Wood Foundation

PWF = Pressure Treated Wood Foundation

PWF = Preserved Wood Foundation
PWF = Preserved Wood Foundation

PWF = Permanent Wood Foundation

PWF = Permanent Treated Wood Foundation

It’s no wonder we can get ourselves into so much hot water.

[plesieur (Paul Lesieur, CMI)]

Funny Leonard

The last link is one of the people I did domes for. They were called the Big Outdoors people back in 1978/79.

I ended up doing a few dome homes because anyone who had finished one was hard to find.

You would build the foundation, frame and deck the floor and backfill.

Would love to see them homes now. Trimming out a dome home was a mathematics nightmare.

[eschmidt (Erik Schmidt)]

Permanent Wood Foundations installed in Alberta once had a 75(?) year warranty issued by the plywood manufacturers association (now bust), maybe check to see if they did so in Regina as well and whether the warranty is still valid. Personally I would have no concerns about PWF providing they were installed right. They are exceptionally warm compared to concrete, no cracks either

Wood foundations have been used In Europe since before Roman times, they can last for hundreds of years. Almost all of Amsterdam’s stone buildings, even bridges have wood pile foundations. http://www.bostongroundwater.org/uploads/2/0/5/1/20517842/2012_09_journal_of_cultural_heritage_underestimated_wooden_foundations.pdf

[Andrew_Huculak]

I now have a PDF of the construction drawings… how do I upload them?

I talked to the original owner/builder who says the house was constructed according to these drawings which I’m hoping someone will review and provide any thoughts they may have,

[dcossar (Douglas Cossar, CMI. NHI)]

@Andrew_Huculak

I now have a PDF of the construction drawings… how do I upload them?

I talked to the original owner/builder who says the house was constructed according to these drawings which I’m hoping someone will review and provide any thoughts they may have,

Nobody is going to tell you what to do about the purchase of this home. That is your decision!

I really think the input you have been provided should give you enough information to make your decision.

This message board is not, and should not be used to obtain free consultations.

Pay someone to provide the information you require!

Cheers

[Andrew_Huculak]

@dcossar

Nobody is going to tell you what to do about the purchase of this home. That is your decision!

I really think the input you have been provided should give you enough information to make your decision.

This message board is not, and should not be used to obtain free consultations.

Pay someone to provide the information you require!

Cheers

You’re right… the ultimate decision will be mine alone. I am, however, looking for views from potentially ,ore than one person on something in the drawings I’m concerned about, and I’ll tell you what it is.

The information I’ve received so far says there is NOT supposed to be weeping tile used with these foundations, but that’s exactly what this foundation has. It was built in 1983, about 4 years or so before the standard came in suggesting drainage holes to let any any water through the footing into a sump hole in the basement floor, where it could be pumped out or drained away.

This house has 2 weeping tiles coming into a sump hole n the basement floor, The sump hole has a sewer cleanout in it, and a backwater valve to let out any water that comes n from the weeping tiles.

My question is, how bad, if at all, should I consider this setup which does not conform to standard developed, (i.e. no weeping tile) a few yaers later?

[dcossar (Douglas Cossar, CMI. NHI)]

Read my previous post!

Pay someone to provide the information you require!

Hire someone who is an expert in this area and PAY THEM for their time and expertise!

Do you understand?

Cheers

[linkster (Leonard Inkster, CMI)]

@Andrew_Huculak

You’re right… the ultimate decision will be mine alone. I am, however, looking for views from potentially ,ore than one person on something in the drawings I’m concerned about, and I’ll tell you what it is.

The information I’ve received so far says there is NOT supposed to be weeping tile used with these foundations, but that’s exactly what this foundation has. It was built in 1983, about 4 years or so before the standard came in suggesting drainage holes to let any any water through the footing into a sump hole in the basement floor, where it could be pumped out or drained away.

This house has 2 weeping tiles coming into a sump hole n the basement floor, The sump hole has a sewer cleanout in it, and a backwater valve to let out any water that comes n from the weeping tiles.

My question is, how bad, if at all, should I consider this setup which does not conform to standard developed, (i.e. no weeping tile) a few yaers later?

You seems to be awfully concerned. You obviously also have way more information than you are providing here. Yet you are asking for opinions based upon, what essentially to us is hearsay (on your part).

It appears from what I read on this thread, (forgive me if I’m mistaken) you’ve already made up your own mind with respect to the issues. You’ve already identified more than you are providing information on, yet are expecting advice from people who are working solely on that limited information.

We are inspectors. We inspect. We inspect visible components, and while some may have experience in drainage, PWF foundations and the like, none of us have a crystal ball, x-ray vision or a time machine.

We cannot determine if your foundation WAS installed properly. We cannot determine if weeping tiles WERE installed or not and ifso at what time in the past or for what reason. We cannot tell you what to think.

As my Colleague Doug Cossar has said, what you need is a more intensive, foundation and drainage specific inspection, using a basement drainage specialist, and possibly an engineer to inspect your foundation further and opine of their findings.

If you had been completely upfront from the get-go, and provided all the information, drawings, photographs and other information at your disposal, you might have manged to solicit an answer that fitted your needs.

With the information you have provided in fits and spurts, it’s no wonder you still haven’t appeared to get information that gives you anything more than you are already aware of.

Spend the circa $1,000 on the basement drainage specialist, they will no doubt be able to pipe your drains, sump and weepers and tell you what’s going on below the surface.

Spend the cicra $1,000 on the engineer who will no doubt be able to opine of the structural integrity of your PWF foundation.

If you called a professional home inspector to perform a purely visual inspection of your home, I suspect that’s exactly what they would opine on.

If you are in that much doubt, walk away.

[dcossar (Douglas Cossar, CMI. NHI)]

@linkster

You seems to be awfully concerned. You obviously also have way more information than you are providing here. Yet you are asking for opinions based upon, what essentially to us is hearsay (on your part).

It appears from what I read on this thread, (forgive me if I’m mistaken) you’ve already made up your own mind with respect to the issues. You’ve already identified more than you are providing information on, yet are expecting advice from people who are working solely on that limited information.

We are inspectors. We inspect. We inspect visible components, and while some may have experience in drainage, PWF foundations and the like, none of us have a crystal ball, x-ray vision or a time machine.

We cannot determine if your foundation WAS installed properly. We cannot determine if weeping tiles WERE installed or not and ifso at what time in the past or for what reason. We cannot tell you what to think.

As my Colleague Doug Cossar has said, what you need is a more intensive, foundation and drainage specific inspection, using a basement drainage specialist, and possibly an engineer to inspect your foundation further and opine of their findings.

If you had been completely upfront from the get-go, and provided all the information, drawings, photographs and other information at your disposal, you might have manged to solicit an answer that fitted your needs.

With the information you have provided in fits and spurts, it’s no wonder you still haven’t appeared to get information that gives you anything more than you are already aware of.

Spend the circa $1,000 on the basement drainage specialist, they will no doubt be able to pipe your drains, sump and weepers and tell you what’s going on below the surface.

Spend the cicra $1,000 on the engineer who will no doubt be able to opine of the structural integrity of your PWF foundation.

If you called a professional home inspector to perform a purely visual inspection of your home, I suspect that’s exactly what they would opine on.

If you are in that much doubt, walk away.

Got the picture yet?

Cheers