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2 Answers

Matte finish paint disaster: Options for more durable finish needed!

Well this is slightly embarrassing, but I either talked myself into or go talked into doing matte finish paint for my entire house. We liked the look of the matte paint as we thought it would hide imperfections and looked kind of rustic to match our Tuscan house theme.

The paint is advertised as "eco friendly" and "washable flat" is its name. Its from Cloverdale. It also has "ceramic microspheres" or something that is supposed to make the paint super durable and its a breakthrough in matte finish paint.

Asked By Mark Helmrich | Aug 28 16
3 Answers

Stand-alone infloor cooling system?

I live in northern Canada. It does not get hot very often, but when it does we can get 90-100F for a few weeks or even a month.

I've got full radiant heat system with 8" OC spacing for heat pipes, many zones and a very snazzy pump setup. I've also got 4 HRV's keeping the air moving.

The infloor heat works great, and I find it very efficient.

For the few months of the year where its hot out, the house can get hot. Depending on the room, it can become un-usable. This of course has to do with all the windows and the solar gain. Hey, I like a bright house :-)

Asked By Mark Helmrich | Aug 28 16
6 Answers

ERV and humidity

This is more for my own curiosity.

I've read that ERV's are generally suggested for warm humid climates and I've also read they can cause humidity levels to rise within a home. My understanding is that with an ERV some moisture is transferred from the stream that contains higher levels of moisture to the stream that contains less. Does the system medium look to balance the amount of humidity between both streams?

Example, Stream A is at 40% RH , Stream B is at 20% RH, ~10% is transferred from A to B where both end up at ~30% RH)

Asked By Chris M | Aug 25 16
5 Answers

Options to make space for exterior insulation

This is my first post so thanks in advance for any input. I’m finalizing the plans for our new home with in Kentucky, and I’m talking through the option of adding 2” of Roxul Comfortboard on the outside of ZIP wall sheathing with the builder. He has never done this before, and one of the objections he is raising is that it would require making the foundation/basement walls 2” thicker to make room for this since we are already planning on a brick cladding.

Asked By Brad White | Aug 26 16
1 Answer

Cathedral unvented ceiling in California

I live in Santa Barbara, CA (ideal climate) and I am remodeling a home. The roof was built in 1975 by the prior owner. The roof from top down and ceiling are comprised of shingles, paper, 1/2" plywood sheathing, 3/4" foam board, then 1 3/8" tongue and groove. All materials are sandwiched together with no air gaps. The roof is supported by exposed rafters/beams.

Asked By Jeff Swaim | Aug 28 16
4 Answers

How to grout concrete block wall?

My foundation stem wall for a raised-floor house is four courses high, made of 8x8x16 concrete blocks with #4 vertical rebars every 4 feet and a #5 rebar in the bond beam top course. I've installed grout stop over the unreinforced vertical cells. After two days of searching, I haven't found any step-by-step instructions on how to grout the reinforced cores and the bond beam, but I have gleaned a few tips to supplement what seems fairly obvious about the procedure. Does the following overlook anything important?

Asked By Jeff Cooper | Aug 27 16
3 Answers

“Smooth” flex duct

I understand that flex duct is bad in most situations--it decreases blower efficiency and just generally impedes air flow. That said, for a longish (25ft) run of 6" duct, I wonder if it wouldn't be okay to use one of the 'smooth wall' plastic ducts on the market (see http://www.flexaust.com/product/grass-collection-vacuum-hose/) for a good example of what I'm looking at. This would be in a relatively low-pressure type of situation (Minotair hybrid HVAC system installation).

Asked By Jonathan Nagar | Aug 26 16
7 Answers

DIY heat recovery and ventilation question

Ok..so it's been a while. We completely destroyed and then rebuilt our 1800s house and aside from some trim and exterior improvements...we have been comfortably living in it now for over a year with many thanks from this site. We used the cut and cobble insulation system combined with blow in with a mooney wall to keep our house very energy efficient. Even in the deep cold of winter our heat bills are below 100 bucks in a 1400 square foot house built over 135 years ago.

Asked By Geoffrey Cook | Aug 24 16
1 Answer

New PHIUS Standard & Small Homes

Is it true that the new PHIUS standard utilizing WUFI, has a bias towards small houses (under 1,000 sqft)?

Running the software calcs shows that the same small home, with the same R-Values, will FAIL to make the PH Standard while increasing the square footage and keeping all other variables the same, will PASS the PH Standard. Even when the R-Values were increased on the small house, it still failed to make the PH standard.

So it seems that the software has some type of "bias" built in for smaller homes?

Could it be a glitch, since the software is so new or is it something else?

Asked By Peter L | Aug 27 16
1 Answer

Can you use rigid insulation only? Exterior wall in zone 1

We are enclosing a screened porch, reinforcing exterior walls on a 1969 trailer and then we plan on putting up rigid insulation over plywood sheathing and existing aluminum

Asked By Jennifer Earp | Aug 27 16
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