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5 Answers

Vapor drive and porcelain tile exterior walls

The nice thing about building a house on one's own is that the building gives you feedback before the finishing touches lock things in. One such lesson for me is summertime vapor drive. I have had Durock CBUs installed over vertical 1x3 furring for some time now with plans to install veneer stone later. The rainscreen gap is ventilated below and above and the insulation behind is closed cell spray foam, so no moisture drives into the house.

In GBA Pro help | Asked By Edward Mallett | Jul 24 17
3 Answers

How best to handle wet garage wall ?

I have a free standing garage that has poured concrete walls. The garage is built into a steep hill side that opposes the back of the garage and one side. I intend to convert the garage to a wood shop where I will store lumbar so I am trying to mitigate moisture issues. The garage has a new roof and interior spray foam in the rafter bays. My problem is that an area about one foot wide on the floor adjacent to the back and the hill side wall stays damp and the lower portion of the same two walls is damp for about 18 inches in height.

In General questions | Asked By W. Timothy Ward | Jul 23 17
28 Answers

Cheapest way to build net zero house?

Hi. I have some questions about building an affordable net zero energy house. I will present a basic outline of my plan, and then ask some questions. In addition, I welcome any comments on any parts of the plan which could use adjustment.

Note: I am not a professional and only know what little I know from browsing these and other websites.

In Green building techniques | Asked By user-6877304 | Jun 28 17
2 Answers

New bath fan vent placement - seeking advice

We have a first floor bathroom on the home's gable end that currently lacks a vent fan. I plan on installing one next weekend, but am seeking advice on the fan's exterior vent placement.

I think I have two options:

1) installing a ceiling fan and running a 12-ft rigid pipe through/parallel with the floor joists and out the back end's vinyl siding. This places the exhaust vent ~10-ft below my attic's soffit vents.

2) installing a thru-wall fan through exterior brick.

In General questions | Asked By hankla.lzo | Jul 24 17
3 Answers

What is the best way to reduce heat gain in South facing garages?

This forum has had a lot to say about how foil bubble radiant heat barriers are silly and a waste of money.

I'm interested in reducing the heat gain in my South facing garages from the intense high desert sun. My garage bakes, and my neighbors is quite cool and comfortable, for a garage. I know he has done attic ventilation above the garage, and installed a radiant heat barriers on the door.

In Energy efficiency and durability | Asked By pshyvers | Jul 22 17
5 Answers

Foil faced rigid insulation

I am in mixed-humid (Zone 3A).

I plan to use foil faced roof sheathing in my vented attic as a radiant barrier and was wondering about the efficacy of foil faced rigid insulation on my exterior walls facing the air gap to the siding (brick, stone and plank). Given my climate, any wall moisture will typically dry to the interior, so it would seem the reduced permeability of the foil facing would not be an issue.

From inside out:
• Latex paint
• Drywall

In General questions | Asked By pnjfksx | Jul 22 17
5 Answers

Insulation and new codes

Planning a renovation and addition of an existing house;

1. Climate Zone 4 - the new insulation code for ceilings is R49. Is the only way to achieve this in 2x12 roof framing to use closed cell spray foam or rigid on the exterior? Client doesn't want to use spray foam. Working to match existing roof lines and not remove the existing roof. In order to match existing roof lines there is part of the ceiling that will also be the roof.

In Building Code Questions | Asked By S G | Mar 3 17
0 Answers

Main stack venting

I'm finishing tying in an addition to my existing slab on grade home and found the main stack vent on the existing house is about 6" into what will be a hallway.

The original house had a 3" main stack vent off the master bath, near where the drain exits the house to the septic. There is also a 2" vent on the other side of the house connected to the kitchen and another full bath. There is a 3rd full bath in the middle of these two vents. The original master bathroom piping has been capped and covered with concrete, except the main stack vent.

In Building Code Questions | Asked By Mike M | Jul 22 17
0 Answers

Accessing a concealed duct unit

My HVAC contractor will be installing a Fujitsu 9RLFCD and a 12RLFCD. Each of the slim duct units will share space in closets and hang vertically. I don't have a utility room for them to be exposed in.
Now I need an idea on how to conceal the slim ducts but still make them accessible.
Do they need ready access like a breaker panel or can all the seasonal coats be hung in front of them? Are there pre-made access panels for sale?
What is a "good practice" for finishing these off? Any pictures?
Thanks.

In General questions | Asked By Mark Walker | Jul 22 17
2 Answers

Naive question on LEED certification

Hi GBA,

In General questions | Asked By Brian Gray | Jul 21 17
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