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4 Answers

Sun Pump solar heat pump

Does anyone have experience with the Sun Pump solar heat pump, either with the product itself or dealing with the company? It's a relatively new company located in Vancouver BC.

Asked By Peter Schonherr | May 19 16
7 Answers

Stamped concrete patio near foundation

Hi all,

I have a couple of questions regarding a patio near the foundation of our house. My wife and I have been dealing with water issues in our basement/crawl space for a while now, and we just recently had a contractor in to seal the vent properly, install a membrane along the foundation wall, and add French drains tied into the downspout.

As the last part of this work, we have removed a surface deck that the old owners installed and are looking to install a stamped concrete patio with the same dimensions (14x30) pitched away from the home. Specifically my questions are:

Asked By Ryan Lambert | Mar 19 16
3 Answers

Fan Coils and Return Air From Framing Voids

Dear Advisor,

Asked By Dan Cullen | May 23 16
0 Answers

Metal roof and wall assembly in Los Angeles

Could you advise on my roof and wall assembly? I want to do better than code and local building conventions (leaky stucco houses) , but don't want to: (1) waste money since the climate is mild; (2) make inadvertent mistakes by diverting from what's tried and true here, and by indiscriminately applying lessons that are meant for more severe climate.

What's your opinion of the most cost effective spec for this climate?

Asked By Claire L. | May 23 16
15 Answers

Has anyone ever kept sheathing warm and saved labor costs this way?

There are a handful of manufactures who make rigid insulation with OSB bonded to the surface (like a SIP with OSB on one face only. But SIPs are not the topic in this post). This assembly is commonly used for roofing but I was contemplating using it backwards as exterior wall sheathing. By backwards I mean fastening it onto the studs so the OSB is touching the studs and the foam is on the outside. By doing this, the osb is kept warm and that desirable thermal break is incorporated as well (after all thats generally the reason to put rigid on the outer face).

Asked By sean stewart | May 22 16
6 Answers

Mitsubishi minisplits — horizontally ducted

Sorry - I blv I posted the same in another section. Please ignore this question if it's a duplicate.

We are not fans of ductless units. Therefore, we opted for the hidden horizontally ducted units that Mitsubishi provides. Unfortunately, all the Mitsubishi contractors we talked to have never designed a home with these type of units. Plenty of ductless experience.

Asked By Ismail Mohammed | May 21 16
19 Answers

Why is our home so inefficient?

We bought an 1,800 sq. foot house in the north Berkeley hills in November of last year. There was a small mold issue which we remediated in December and January. During that time we also did an extensive HVAC upgrade, with a 3-zone heating/cooling system, smaller/more efficient duct work, an in-line dehumidifier, and in-line air filter. (Our daughter is sensitive to mold and other airborne allergens, which is why we installed the dehumidifier and air filter.)

Asked By Chris Durand | May 22 16
14 Answers

HVAC - Gas vs heat pump vs ducted mini split

It seems the general consensus here, on a very tight or "pretty good" house, is for ductless minisplit. I'm trying to understand the economics.

The following parameters are non-negotiable:
1. Climate zone 3A
2. The house will be piped for natural gas for, at a minimum, cooking and outside grill

Asked By c l | May 22 16
8 Answers

What would a weighted average R-value be for a Superior Wall Xi?

I am trying to determine what the weighted average R-value of a Superior Wall XI and XI plus wall is. Does anyone know? I can post cross sectional diagrams if someone can tell me how.

Asked By Chaz Steffen | May 23 16
7 Answers

Fastening details - deck ledger to insulated slab

I am designing an insulated Monolithic Slab. I plan to install 4" of Roxul comfort board beneath and around the perimeter of the slab.

Does anyone have experience attaching a deck ledger to a slab (or stem wall) that is insulated with Roxul? Or is it advisable to place a higher density product beneath the ledger to avoid compression which may happen with the Roxul Comfortboard?

What type of fasteners are recommended for this application? Would a standard wedge type concrete fastener like a red head work?

Other solutions?

Asked By Michael Iacona | May 19 16
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