Attached are 2 pictures from an inspection I did yesterday. I found moisture under the vapor barrier, in fact there appears to be a second vapor barrier beneath this one. There was a moisture problem before and a French Drain was installed around the perimeter, several years ago, and I believe this vapor barrier was installed at that time. The one picture shows the mushroom and the fuzzy mold around its base. The second picture shows the 1st floor 1/2 bath exhaust fan vent discharge just above and to the right of the shroom. 1. How “moist” should it be under the V/B? 2 V/B’s is that acceptable or does that present any issues? On the report because of the mold I was going to recommend further investigation by a certified mold inspector. The wood flooring and associated supports looked fine and did not show any signs of mold or moisture damage. Thanx in advance for your comments!!
Home Inspections of Martinez Inc.
According to HUD, the vapor barrier needs to be lapped up foundation walls , piers and at seams at least six inches. There should be no exposed ground.
As far as moisture there should be very little. No standing water should be under vapor barrier.
Make sure the crawlspace is well vented. If below ground on most sides, a power vent will need to be installed on one end of the crawlspace, if conveniently vents can not be installed. You want to create a negative air pressure with the fan.
At least note the mold and make sure the customer knows about it. Let him make the call for testing the interior. Getting the crawlspace air tested is useless because it will probably test toxic. Only be concerned about the air in the interior of the home. Have the customer sign the NACHI mold waiver if the client decides he does not want to test.
My Industrial Hygienist, who is certified in mold, recommends a power vented crawlspace on one end. These ideas that you have posted are right in theory. It is like wrapping a house on the outside tight. As long as the barrier does never get a hole in it the theory will work. I have not seen too many old barriers without holes in them. Houses do not breath know days. We are killing ourselves with our own air. Besides have you ever priced a sealed barrier like are in the articles. The last job I was involved in with a sealed barrier, counting the sump pump and the dehumidifier, was about $30,000.00 . The home owner will never get his money back. Most of the time simpler is better.
It is always much simpler to build very loose houses without insulation and air/vapour barriers but…ask folks if they want to pay the heating/cooling bills.
I find about 99% of contractors have not retrained in energy efficiency, building science, air quality, residential ventilation, good building practices as opposed to code minimums, and on and on!!! Why??? They have to take time off work and have to re-think the partially correct/incorrect and incomplete information they learned 10-40 years ago!! It’s a loss to just about everyone buying a new house these days!!
Michael, I made a personal observation. I feel that it may be accurate since I am in the field quite a bit (doing litigation pictures presently and writing reports 'til late tonight) …in litigation, inspecting, dealing with building officials. In the last 4 days, I have had calls for information from (1) the architect responsible for the building codes in our province and (2) a provincial Energy Program Administrator about ideas for a new directive they’ve been given. Hell, I haven’t worked for them directly for 8 years although I did finish a contract for them March 31/08. I must be considered to be quite current by these folks as they still call for info!!!
Come to think of it…my stat is probably wrong. When I find the** ONE **contractor that has trained in all these fields I will say 99% of contractors have not retrained. Until then, it’s much closer to 100%.
Hi Brian…what you say may be happening on the East Coast, but from what I’ve seen in the last 10 years, many reputable builders are continuing their education at night. Many courses offered at the community colleges are full.
I used to drywall for 9 builders exclusively, all were using current technologies. The newer builders learned during their apprenticeship, the older ones learned from the apprentices.
Then I move up here to the sticks and it’s like it’s the 70’s all over again. Trying to get something current at a local lumberyard is like trying to pull teeth from an un-sedated pitt bull. The locals never heard of half the stuff I ask for.
Like Blue-skin, ditramat, resilient channel, No-Coat vinyl tape. Sure they’ve heard of it, but the contractors haven’t so they dont stock it.
Oh well…c’est la vie
Here we have the Blueskin and the others but having it is different than knowing where and how to use it. The litigation I worked on in Oct/Nov, an $800,000 house, was rotting over 2.5 stories in 7-8 months because of the improper use of Blueskin while trying to do a “better job”. I was called in (after being recommended to the owner by Dalhousie University Faculty of Archtitecture) as they were putting the the rotted pony wall/first floor rim joist back in for the first time. At the point I arrived, they had already re-attached the deck to the joist area, so had to got to the basement to take down finished family room ceiling to gain access to the rim joist from inside. Found high wood moisture and still active wood decay fungi…for legal purposes, called in my favourite Phd. mycologist…this is after 2 engineers had already been on site!! I felt a bit like Mr. Holmes…“It’s all got to come down!!!” Other problems included HP/AC & HRV not being properly sized, contractor’s falsely advertising installed insulation R values.
The litigation I’m now working on (doing the pictures this PM),…a design by an award winning archtitect, had the worst ventilation system/HRV installation I have ever seen…period. (Started installing HRV’s in 1981 and have been HRAI certiifed since 1984-5 as well as being an R2000 inspector/researcher for 8-9 years) This is only one of the major items on a smallish commercial/residential building of 3000+ sq ft!!
Having worked with more progressive construction and energy efficient techniques since 1977, gives me a lot more experience than most and a much more critical eye…so I say again, not many have really taken all the training necessary to obtain the understanding to put together truly energy efficient, better homes that are durable, materials efficient, green and will last without some major hiccup occurring!! I don’t see this in more expensive homes and I know it’s not happening in starter homes!! Are these types in your area??
I somewhat agree, but you have to consider that proper building in the south (Florida, Texas Gulf) is different from my area (Chicago, right by a great big lake) from the high desert of Colorado anf from the atlanic coast.
There is no “ONE” right way to build. Local ground, climate and traditional building techniques must be brought into account.
I know of an architect whi si building his “dream” energy efficient house. Solar everything and geothermal everything else. I did many draw inspections on the place and git to know this guy. He studies ALL the literature and all the latest techniques and materials.
But he got the house totally wrong.
Mold all over the place, eating is huge (8 x 12) wooden timbers. Liquid water dripping down from between his “separate envelope”. Cold in the winter and really hot in the summer. The place is a freakin’ mess.
If this guy (he even teached architecture and “green” building at a local University) gets it wo very, very wrong, how can you expect a builder to get it right.
Ultimately, the architect is responsible for the condition of the house. I, regularly, see plans that are only 6 pages long. No detail drawings. They leave it up to the “builder” to fill these in. I almost never see the proper flashing around windows and doors and they rarely tape the window and door openings, or even the Tyvek seams.
The reason? The architect didn’t “require” it in the plans and the local AHJ didn’t “require” it.
So, who is really at fault, especially in a state like ours where there is no technical education requirements for GCs.
This is why HIs have to keep abreast of the latest info.
We, also, have had 2 consecutive warm and wet winters in this area. I am seeing, more and more, brick veneer walls that are really wet and spalling. They never had the proper 10 - 15 days of single digit temps, in the winter, to dry out properly.
So, while a real problem, I would not blame the builders exclusively. Blame the big guys (the Architects) who have the big insurance policies :mrgreen:
,As you see in my post, I did include an award winning architect’s building. Yes, it must be spread around but I see the most resistance to change in the contractors’ trank or they change/supply new solutions using their know-it-all attitude…that’s what happened in the first $800,000 house I mentioned with severe rot in 7 months in a cool, moderate climate…down south it would’ve rotted in less than 2 months!!! We need required, verifiable-by-proctored-exam CEU’s in the “new” basics of building science for all building professionals.
You guys have taken some courses in building science from IR guys. I’m thinking of taking one just to hear what’s being taught!! I have some suspicions…but then I might be pleasantly surprised!!! Which would you recommend?
While ia like, read and work to understand all of Joe’s stuff, he is just one guy.
I will take what he provides and examine it and work to check it, but to totally swallow it is just to drink the Kool-Aid.
Most of his work describes conditions in the south. I don’t live there.
I see the old triple wall brick buildings, built in the 1890s and the look pretty good. Joe’s work has no explaination for that.
I also see 1888 George Maher original foursquares (many in this area) with the original stucco (concrete based) over wooden lathe that is still fresh and good as new (although a little water stained). It was built with old growth Wisconsin pine and will probably last for another 100 years.
we really have to do some work to change this paradigm. the architects are not, the engineers have been relegated to only structural work and there are very few actual “building scientists”.