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1 Answer

Why is this brick eroding?

I have an interesting thing happening to my brick chimney. We noticed that two of the bricks, their faces, kind of crumbled off. Not the white powdery residue but actually powdered off in the same color as the brick. Looking for a reason why this might be happening. We live in Missouri (St. Louis). In the pictures the picture labeled "Brick 2" is what the effected brick looks like. The other picture is a typical smooth brick on our chimney.

In General questions | Asked By Richard Hogan | Jun 11 16
7 Answers

Alternatives to TimberSIL

We are designing a commercial project in Gulfport, Mississippi where we were planning to use TimberSIL. We were looking for something that was durable, low-maintenance, and highly resilient in addition to being environmentally friendly. We chose TimberSIL since it was one of BuildingGreen's Top Ten Green products several years ago, was the first non-toxic preservative product approved by the EPA, had been around for over a decade, and seemed to have one of the best warranties available among pressure-treated woods.

In Energy efficiency and durability | Asked By Heather Gayle Holdridge | Dec 30 13
5 Answers

Framing factors

I am trying to calculate framing factors for walls. I read that until 1993 ASHRAE recommended using 15% for 16"oc walls and 12% for 24"oc. Then in 1993 they revised these to 25 and 22. Is this still what people are using? Also, how does this change for walls that use advanced framing techniques? Is there any resource that gives this information?

In General questions | Asked By Amanda Evans | Sep 11 10
2 Answers

Identifying this 1957 panel for insurance purposes

Due to hail, we are working on a number of homes built in 1957 in southern NM. These are block homes with purlins 32" OC and what appears to be 2" Tectum 1 panels from way back when.

We plan on going back with the 8.25" R Control panels to meet the IECC building code of R-30 for the roof/ceiling assembly, which will be a huge upgrade for these homes. What we really need is to properly identify these panels for insurance though. Please see the attached photos.

Thank you in advance.

In General questions | Asked By Justen Newton | Jun 10 16
4 Answers

Multiple vapor barrier approaches in one house

I am building a small house in Southeast Alaska (mild, wet maritime climate). The walls will have R21 fiberglass batt insulation and 1 ½" of interior polyiso foam. The R-Max foam will also act as a vapor barrier.

In Energy efficiency and durability | Asked By Justin Smith | Jun 9 16
4 Answers

ROI for insulating 2nd floor walls

Hello GBA,

Fair warning that the answer to my question may be "as you wish" since there are very personal reasons for deciding one way or the other, but I am hoping for some advice that is able to balance the ideal and the practical.

In General questions | Asked By G S | Jun 9 16
2 Answers

Rigid foam over textured concrete basement wall?

I think the standard advice at GBA about insulating basement walls is to put rigid foam flush against the basement wall, and then install some sort of fire barrier, e.g. drywall. The key is to prevent moist air from contacting the cold basement walls and then condensing.

In Energy efficiency and durability | Asked By andrew c | Jun 9 16
1 Answer

Insulating catheral ceiling

Hi, I"m working on insulating an addition that is cold in the winter. It is an addition to the back of a standard rectangular ranch. One half of it is a covered patio, and the other half is a dining area. the dining area. The dining area has a cathedral ceiling, and a knee wall above a sliding door. The area above the covered patio is a vented attic. The knee wall in the dining area separates the dining area from the vented attic.

In Energy efficiency and durability | Asked By John Gifford | Jun 8 16
4 Answers

Plastic sheeting under concrete wall against existing foundation

So when i put up my addition, the addition's foundation is a full basement. It will therefore be somewhat below the height of my century home's existing basement. To prevent underpinning and generally expensive problems, we are installing a step in the foundation where it butts up against the existing wall. This way the wall is still supported, the addition can be the depth i want it to be, and I dont have to worry about the expense of underpinning. And i have a handy shelf once its done. :)

In General questions | Asked By Terry Sharpe | Jun 7 16
2 Answers

Can I install a minisplit heat pump away from the house?

We have been planning on installing a mini split in our small 1890's New England home we are energy retrofitting. But we are looking at some significant barriers to putting the heat pump on any of the sides of the house (set backs, DPW regulations on the width of the driveway, and future renovations on the other sides.) Can we put the minisplit on the side of a shed across the driveway and run the lines to the house underground? One contractors suggested this, but others are offering different reactions to its possibility. I am not sure what advice to take on how to go about this. Insights?

In General questions | Asked By Marie Brown | Jun 7 16
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