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10 Answers

Sound attenuation between floors

I am constructing a floor assembly between a 1st and 2nd floor and may not be able to build up a deep floor assembly due to exposed ceiling timber joists (and the small footprint of my structure). I am considering using 2 courses of Advantec (subfloor) material with perhaps a mass loaded vinyl material in between the subfloor material.

I was wondering if anyone else has constructed a floor assembly that might reduce some of the sound transfer without resorting to a deep floor framed system. Has anyone had success solving this problem?

In General questions | Asked By John Brown | Mar 15 17
0 Answers

Exterior foam and Roxul batt on a reno

Have a client who has an older house he just purchased . Scarsdale NY . He intends to put 1" rigid foam outboard of the sheathing with Tyvek behind and 1x strapping to attach siding .

Interior first floor walls are 2 x 6 , second and third floor are 2 x 4 . Question 1 is what R value Roxul should he use in the 2 different wall assemblies ?

Second question is , is Tyvek the right product to use as the only barrier between the sheathing and exterior ?

In General questions | Asked By Richard McGrath | Mar 22 17
10 Answers

Hydronic Heating System Hydraulic Buffer Tank vs Hydraulic Seperator

This question might be more appropriate in a plumbing forum but I have had such great and thoughtful responses in the GBA forums I look to here first. This is also a hydronic heating mainstream topic which should be appropriate for GBA.

In Mechanicals | Asked By Roger Smith | Feb 26 17
9 Answers

Do magic boxes distribute loads for ductless units?

For my pretty good home I am building( 2150 sq.ft. Zone 5 northern ct. near Sturbridge mass) I have recently got a quote back for mini splits. 5 heads 2 outdoor units Mitzi. Hyper heat. The contractor is at 17k installed. Diamond dealer. He has one head in each bedroom and 2 on the open floor plan. I am curious if there is a way to quantify how much a ducted ventilation system mixes the air around the home? Would a Minotair or cerv balance out the heating and cooling requiring more like 2 or 3 heads?

In General questions | Asked By Scott Mangold | Mar 20 17
2 Answers

Insulating floor of an old barn

I have an 1804 bank barn and plan to use the lower level as a shop. Since dirt falls through the floorboards above anytime I walk upstairs, I need to think about insulating as a first step.

The easy thing would be to spray open-cell foam on the ceiling (bottom of 1.5" floorboards); but, I'm concerned that the foam won't maintain an air seal when people and machinery move around upstairs.

In Energy efficiency and durability | Asked By Michael Stelts | Mar 22 17
20 Answers

Do I need to put rigid foam on a crawlspace dirt floor?

I live an old 1890s brace/balloon frame in Virginia (Climate Zone 4). Do I need to put rigid foam on the dirt floor? My contractor is adamant that I need to either insulate the dirt floor or the ceiling above to be compliant with IECC. I was under the impression that I could put a vapor barrier on the floor and insulate the walls with rigid foam. Is there a best practice? And if both are acceptable, how much of a difference does the rigid foam make to the comfort/cost savings? Thanks for any input!

Chris

In Energy efficiency and durability | Asked By Chris Thomas | Mar 21 17
9 Answers

Metal siding — window head flashing detail

OK this keeps resurfacing so I thought I would see what others have come up with. When using metal siding (corrugated or sim.) dealing with the window head always seems to be a bit of a conundrum.Typically I see a piece of "J" flash utilized. But this usually points up, which may conceal the cut of the cladding panel, but consequently also catches water. Seems wrong. I have been trying to come up with an alternative and drew the attached, but surely someone more intelligent than I must have devised a better solution for this issue ?

In General questions | Asked By Erik Lobeck | Mar 21 17
17 Answers

Ultra-Aire XT105H vs. Honeywell DR90A2000

I've seen much praise of the highly efficient (most efficient?) UA XT105H whole-home dehumidifier in my research. It certainly seems like a winner. As with many things, though, having the best often comes at a price and the XT105H seems to be no exception to that rule. See below for the specs:

http://s7d2.scene7.com/is/content/Watscocom/Gemaire/article_142249153705...

In Mechanicals | Asked By Lance Peters | Mar 1 17
10 Answers

Air King Introducing most efficient fan?

I was mulling around on the Energy Star website and came across a listing for an Air King in-line fan. Curious, I checked out their website and also found they have a new line of DC motor exhaust fans coming to market.

According to a page on the 2017 AHR Expo website, these new Air King D4S and D4D fans will be the most efficient exhaust fans on the market:

http://ahr17.mapyourshow.com/7_0/exhibitor/exhibitor-details.cfm?ExhID=1...

In Mechanicals | Asked By Lance Peters | Mar 21 17
1 Answer

how to detect a roof leak after having the underside of the roof deck sprayed with slosed cell?

I live in Buffalo NY and am renovating a Cape Cod style home. The interior is completely gutted and had a roof tear off and GAF system installed with no ventilation with the plans for having the deck sprayed with closed cell. I had a question that no one up here can answer...
As the roof fails or if there is some sort of damage, how will I know if the underside is 100% sealed? My fear is the water will rot the rood substructure and hold mold. Is there any way to create a path for any potential leaks to follow??

In General questions | Asked By cheezlo | Mar 22 17
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