Sunday, January 10, 2010

cottage condensation

Re-Inspection, it's a service that all Home Inspectors should offer. Past clients calls, maybe from years ago. This is not necessarily a bad thing. Many inspectors seem to be very tardy about getting back to past clients. Maybe this is due to the fact that they are worried that they will have a complaint to deal with. Truth is, I get hundreds of calls each year and very rarely is it these people that are trying to hang you with a problem that they have, in fact it is quite the opposite. As inspectors we establish a level of trust with our clients (assuming you are competent ) and they are calling for help, understanding, or direction.
I spend very little money on marketing ( not that that is the making for a good business plan) Where I spend my marketing dollars is somewhat indirect. I eat costs. Case in point, the cost of re-inspects, when I do charge it is very minimal. I leave my clients with the warm fuzzy feeling that they are still benefiting from a service that they may have purchased years ago. Guess what. We have all heard the old saying " They tell two friends and they tell two friends", well you get the idea. And it pays off in spades.
Yes you are correct that is a very strange introduction for condensation problems.
This is one of my typical call backs. Not to place blame, not to hold responsible, and not to point the finger. Just a cry for HELP. "I am frozen out of my cottage, the door is frozen shut, I can't even get my dam key in the lock and all the windows are dripping wet! We had to spend last night in a hotel because we could not access our own cottage!"
Here is the scenario, Clients from the Big Smoke buy a nicely renovated cottage in Haliburton County, the inspection goes well. In this case the cottage has all the tell tales of a "flip".
An old cottage that has been purchased, cosmetically renovated and re-sold in the hope to make an extra buck. Here is the concern. We take and old cottage on piers with an earth floor and a very low slope roof, which at some point has had an addition of a fourth bedroom and another roof built over top of the original one to increase the pitch (or slope) of the roof. Not a bad idea, better snow shedding capabilities, and an increased attic space that allows for increased insulation and adequate ventilation. All the ceiling had been re-drywalled at which time,unfortunately they covered in the attic access (sound familiar, client bought anyway, and a year later still no access, oh well.) The drywallers did a very professional job but strangely enough left the add on bed room with the old paper acoustic tiles. The crawl space had been "skirted in" with plywood and a spray foam insulation had been sprayed on the inside of the exterior walls. As per the inspection recommendations the my client covered the earth floor with a 6 mill. poly to reduce the amount of moisture and soil gases emanating from the earth floor. The crawl space was pretty friendly it had a head room of between 36 to 48 inches in most places, but like most lake side cottages it was built on the side of a hill. This means lots of head room ( from a crawl space stand point) at the front of the cottage ( which would be considered the lake side) and not so much at the back. Inside the cottage new vinyl and laminate flooring was also added. Once again acting on a recommendation form the inspection the client replaced the remaining old window with a high quality single hung vinyl window which were installed very well. The installer even offered to go around and re-caulk all the existing windows and doors, and equally did a very nice job of it.

So you might ask your self " Well Mike, this place sounds perfect. Whats the problem?"

The problem is they now are living in a plastic bubble. No air in and more importantly no air out.
The next question you might ask is, so where is the condensation coming from?
Canada Housing and Mortgage Corporation has an interesting site on their web page that pertains to this specifically, that being seasonal dwellings and condensation. Take a minute and check it out it is an interesting read (

Finally lets get to the meat of this concern. where does the moisture come from?
with continuous use the occupants are the biggest culprits.

BATHING / SHOWERS 2.5 /per shower

However in this case the cottage is being used only during weekends in the winter time.
After the re-inspect was finished the only viable conclusion that I was able to come up with was the addition. The add on was built basically right at grade level. At the back of the crawl space I was able to see where the floor joist (of the addition) were maybe 4 or 5 inches off the floor. There was just no way you were going to be able to thing small enough thoughts to even consider getting into that space. Given the fact that this space was so small the likelihood of getting a vapour barrier on the earth floor or any insulation was going to be impossible. This area was further plagued by the fact that like most of the cottages this was on the down side of the hill so the ground here was continuously being saturated via surface water, weather it was rain or snow melt. Now we introduce the phenomenon of "stack effect". The air pressure that is within and surrounds our homes and cottages ( this will be another writing in the future ) which is always pulling air vapour into our living space that may exist in the lower levels. When there is a high level of moisture laden vapour or air within the building in the winter it is always tiring to get out. If it is not being removed mechanically then it will find its own path, fixtures, windows, doors, attic access, any where that we have a penetration in the building envelope ( the insulated shell). When it hits these cold surfaces the vapour condenses and turns to moisture or frost.
In this case the fix that is recommended:
1 sub floor come up in bedroom to access crawlspace
2 vapour barrier is placed on earth floor (also acts as a drainage layer)
3 earth floor is then spray foamed as well as perimeter
4 Heat Recovery Ventilator (HRV) is installed
I'll let you know how things turn out


  1. Spray Foam Roofing is a common word used in the building industry, but still not as readily used in our market. There are typically 2 types of spray foam used today. One is an open cell foam insulation and the other is a closed cell foam insulation.

  2. You said it just right. Its all our own benefit to inspect our roofs by professional inspection team. Great post. Thanks for sharing.

  3. Hi Michael,

    I am a roofer in Toronto and was called by my city customer to come and look at her cottage up in Port Sydney, Ontario.
    She has been having "leaking" since june and based on the pictures I thought it was maybe ice damming, but given she noticed the leaking in June I was puzzled. Then she told me leaking was coming from the peak where the ridge ventilation was installed. My next thought was maybe that was installed incorrectly.
    She then told me the insurance company was called and they had an engineer who said "condensation" was the trouble. I found this blog post and believe based on your comments it is a few things.
    Her cottage is on the side of the hill
    there is multiple levels
    I am not sure if is was a year round cottage for the previous owners.

    She paid for the road to be regraded, a new 20,000 roof was put on and the roofing compnay has come out several times to fix or upgrade this roof.
    This poor woman is at her wits end as she is looking at 50,000 in interior damages.
    In a desperate attempt to get an "honest roofers" opinion she commissioned me and my roofer to go up a few sundays back.
    There was already a foot of snow up on her roof and from what we could see this 20,000 roof she installed was of excellent quality workmanship and top quality products.

    We opened up the soffits and notice very little insulation and what appears to be wet marks.
    WE know that she plans to use this year round, maybe the former owners only used it in the summer who knows.
    Given you seem to know alot about condensation and cottages are there any questions I need to ask her to get conclusive answers.
    Given your blog I now think it is condensation , can water really "pour" down a wall and through beams if it is condensation?

    I look forward to your response.
    take care