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3 Answers

Slab are not designed for comfort and R-value?

Slabs are terrible to walk on--at work we have concrete floors. My legs and feet hurt after a few hours.
Yet I can walk my dog for an hour on ground and my house is on a joist floor and its all good. So on my addition--a slab is better than a crawl space of 36". I have seen where you can put treated sleepers in and fill between with sheet foam--but wouldn't that make it stiff by eliminating flex? has their been any work done on measuring floor give when you walk on it? Is their a way to replicate a wood floor on the slab that can be rated?

In Green building techniques | Asked By Scout159 | May 16 18
3 Answers


I've just found beetles (see picture). I know the signs, little holes in the wood all over.
This is on a 1925 stucco home in the San Francisco Bay Area fog belt. The evidence was found on a open foundation vent that's not protected from weather (apparently never painted since 1925).

Similar beetle damage appears on a decades old stored wood pile on the other side of the house, which cannot be moved because of the owner.

In GBA Pro help | Asked By Bryce Nesbitt | May 16 18
4 Answers

Ventilation for basement

I recently insulated my basement with rigid foam and have begun framing. My house is heated and cooled with minisplit units and I was thinking that it might be good to have a way to ventilate my basement since I live in New York and opening the windows during summer would introduce a lot of moisture into the basement. The basement consists of only about 500sqft so I was hoping to find something fairly reasonable in price. I saw that Panasonic has a whisper comfort model for around $300 but it looks like that system can only remove and return air from the same point.

In Mechanicals | Asked By Kevin Schramm | May 16 18
8 Answers

Feedback on house layout/orientation

I posted a question several months ago looking for feedback/constructive criticism on a new home layout I was working on. I've tried to incorporate a lot of the advice given into my revised layout. Was curious to see if any of you experts had any further thoughts.

In General questions | Asked By GREG GRIGUTIS | May 14 18
4 Answers

Insulation for a stick-frame roof — but we want the exposed beam look

so we bought a house that was built in the 50s and we had take out the drop ceiling and old drywall ceiling above that to run new wiring.

Bottom line - wife saw the open ceiling and asked if we could keep it that way and ya'll know that saying. Anyways - I look at the roof and it is just 1x6 boards laid across the rafters with a shingle roof on top. Roof nails piercing the wood all over.

So I would like to give my wife the look of exposed beams but I am thinking how do I insulate it. The roof is brand new on the outside, so I don't want to disturb that.

In General questions | Asked By A.J.W. | May 16 18
6 Answers

Multi/mini-split cassette buried under blown in insulation?

I am in the planning phase of a house renovation (San Francisco Bay Area, zone 3C) which includes a new HVAC system and am considering a multi-split system with ceiling cassettes and ducted units. The unconditioned attic insulation is blown in fiberglass on the attic floor. Although not as efficient, the ducted units may have to go into the attic due to space constraints. The ducting would also be buried under insulation. None of the manuals and online references I have found seem to specify whether ceiling cassettes or ducted units can be buried under blown in insulation.

In Mechanicals | Asked By Wilson C | May 15 18
4 Answers


Yesterday I came across this blog: https://junkit.ca/5-things-you-thought-you-could-put-in-the-recycling-bin-but-cant/ which left me in surprise. It says pizza box, water bottle cap, wet paper, aerosol can and so are not recyclable. This is a new knowledge for me. But is it true? I know recycling is important for the earth as well for the future generations to come. So I'd like to start a discussion based on recycling here.

In General questions | Asked By emma3434 | May 16 18
10 Answers

Mitsubishi PVA/PUZ a "Central heat pump" or "mini split"?

Looking to replace my oil fired forced air furnace with an air source heat pump. Cold winters here in MA so I like the Mitsubishi hyper heat units. MA has a heat loan program for 0% financing for 7 yrs with qualifying units (>=16 SEER, >=8.5 HSPF for "Central heat pumps"; >=18 SEER, >= 10 HSPF for "Mini-split heat pumps"). The MXZ-4C36NAHZ is rated at 15.8 SEER and 10.1 HSPF pairing with a MVZ-A36AA7. However, the PUZ-HA36NHA5 is rated at 17.8 SEER and 11.0 HSPF, paired with the PVA-A36AA7.

In General questions | Asked By Scogan | May 12 18
10 Answers

Attic insulation - R-21 and radiant barrier

Hi I know this topic has been asked a lot but I was hoping to get some info I could not really find in other posts.

In Energy efficiency and durability | Asked By msimm15 | May 15 18
9 Answers

When is it necessary to use foil-faced insulation?

I am insulating an exterior wall (8" CMU with direct applied 1/2" stucco) with 1 1/2" rigid closed cell insulation which is placed on the inside face of the CMU in a furred out (1 5/8" metal framing) interior wall. can I use regular closed cell insulation or is this an application which is better suited for a foil face closed cell rigid insulation.

In General questions | Asked By Ebt111 | May 15 18
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