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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.

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?

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.

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?

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.

Asked By boese | Oct 9 17
2 Answers

About Net Zero

I live in Michigan. I have solar panels that supply most of my electric needs, with easy expansion capabilities. As electricity is necessary for me at all times (I live in an area with a high water table and a sump), so far I have remained grid-tied and have a whole-house automatic propane generator for outages.

Asked By Lynn Cummings | Oct 9 17
4 Answers

Programmable thermostat recommendation?

My ranch house in Northern Idaho will have a natural gas fired in-floor hydronic heating system. I also added one zone mini split for A/C needs, but this could also make sense to run during shoulder heating seasons. I've installed a PV system that will produce excess power during most of the year, so at times the electricity to run the mini-split will be "free". It gets complicated.

Any recommendations on a programmable thermostat to use with this set up? I can envision control algorithms using outside temperature and time of day.

Asked By Steve Wolfe | Oct 8 17
3 Answers

Attic floor insulation and vapor barrier with phased construction

I'm looking for help on an attic floor assembly. This is new construction where the attic will not be finished right away. It could remain unfinished for 5 years. I want to install the insulation and vapor barrier to perform correctly for both an unfished and finshed attic detail. I want to make sure the assembly is drying to the correct side.

I have attached a pdf to show the assembly.

Asked By Seth Holmen | Oct 9 17
3 Answers

I've heard that some heat recovery ventilators produce ozone. Is that true, and if so how?

How can you know you are buying one that doesn't?

Asked By mark romwalter | Oct 8 17
1 Answer

What are my options for attaching and protecting foam insulation to exterior concrete basement walls?

I live in an area of frequent freeze/thaw. basement walls have foam insulation that has detached in some places, and has just generally degraded over the past 10-15 years.

Asked By user-6932004 | Oct 9 17
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