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2 Answers

Is my re-roofing strategy adequate?

I just visited the supplier that I'm planning to get my foam board and metal roofing from. I was struggling to decide my strategy before, but now I'm really confused.

I an reroofing a 118 year old bungalow in central Indiana, zone 5. My plan is to tear off shingles to the wood board sheathing, repair, wrap in air barrier/membrane, 2 layers of 2" foam board (probably foil faced polyiso) seams taped and staggered, then horizontal purlins attached with 7"(+) screws.

In General questions | Asked By Dielectricunion | Oct 11 17
2 Answers

Low-slope roof replacement questions

Thanks for this great resource! I am planning to replace a 30 year-old 3-tab shingled roof on a circa 1959 house with a low slope (~2/12) in zone 2A (Houston, TX). I have been reading through a number of the articles relating to cathedral ceilings and low-sloped roofs, but I still have some questions. More details on the roof:

  • The roof has soffit venting but no ridge vents;
  • The roof system consists of two gable-ended roofs (main house plus garage/utilty room) that meet in a dead valley over about a third of the length of the smaller roof;
In Energy efficiency and durability | Asked By BayouMCM | Oct 10 17
34 Answers

Insulating a low-slope roof

Hi Martin,
We are ready here to go ahead with the insulation of our low-slope roof, and decide to go with closed-cell sprayed foam as you recommended.

We had 3 quotes from local company, and 2 of them proposed to shoot 5-6 inches of foam underneath the 1st deck (in green in the following image), assuming we would remove the interior ceiling.

In Green building techniques | Asked By Francois Desrochers | Sep 6 17
13 Answers

What would cause water to migrate up through a slab and “sidewalk”?

We have lived in a slab Foundation house for almost two years. When it rains after a dry period we will have enough water come up through slab that it takes a squeegee to get it under control. This happens right at the carport door entry and about a foot away from a half bath wall, as well as into the first six or seven feet of parking area.

In General questions | Asked By Elaine D | Oct 8 17
1 Answer

Do you offer Continuing Education Units that fulfill requirements for Architect licensing?

I have learned more from your site than any other venue, and would welcome the opportunity to do my annual required education with you.

Colorado licensing for Architects requires 12 hr of continuing education per year.

In General questions | Asked By Vija Handley | Oct 10 17
11 Answers

High humidity in house after insulation


I am hoping someone might be able to shed some light on a humidity mystery. I had my attic insulated with blown cellulose and air sealed ( I hope). Since that time my home has gone from around 45-48 % RH to 52-56% RH humidity ( 73-74 degrees). Also we have an encapsulated conditioned ( dehumidifier and supply vent) crawl with a radon system. The roof has radiant barrier sheathing installed when the house was built 8 years ago.

In General questions | Asked By Hotandhumid | Oct 10 17
4 Answers

Foundation drain tile and filter fabric

Hi all,

So I have finally finished waterproofing my foundation wall (used MasterSeal HLM 5000 its about 4ft below grade). I am going to be adding 2" XPS and then miradrain drainage mat to the outside of that. This leads me to the drain tile and footer. I am planning on running the water to a drywell in the future eventually.

Trying to figure out what filter fabric to use. I have 4" sch 40 pipe and planned on 3/4 crushed gravel to bury the pipe wrapped by filter fabric. Might also add a filter sock as an extra layer of protection.

Any recommendations on which filter fabric to use?

In General questions | Asked By Dan Nospa | Oct 5 17
3 Answers

Interior Parge on Nexcem Stemwall? (Conditioned Crawlspace)

Hi everyone, I am building a house for my sister-in-law in Southeastern Manitoba (Climate zone 7a, Canadian Shield terrain). The foundation wall is formed with Nexcem (formerly Durisol) forms, which are kind of like large CMUs made of cement-bonded woodchips with a rigid mineral wool insert. They are free-draining, vapour permeable, and not air-tight.

In Energy efficiency and durability | Asked By Benjamin Pries | Jul 12 17
5 Answers

"Picture framing" the stud bays with Knauff Ecoseal

Knauff seems to recommend "picture framing" the stud bays to the sheathing with their Ecoseal product. Is there a real benefit to this or does it just sell more of their product?

In Energy efficiency and durability | Asked By Norman Bunn | Oct 6 17
4 Answers

We want to spray our basement ceiling rafters black. We also want to sound insulate using spray on foam between rafters.

My question is can we paint the sprayed on insulation and will paint stick to it.

In General questions | Asked By boese | Oct 9 17
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