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2 Answers

Rockwool insulation in air vents

I was at a home and we discovered that rock wool batts were lining the return vents. Does this pose any concern.

In General questions | Asked By Robert Hronek | Nov 6 15
5 Answers

Minisplit installer recommendations — Massachusetts

Can someone recommend a mini-split installer in MA? I have had six mini split installers (Fujitsu & Mitsubishi) look at my house and each and everyone either wants a head in every room or wants to install supplemental heat in every room. The house was built using the PGH concept but it seems the installers I've come across have no experience in designing a system for one. They all feel that you need heat in every room no matter the load. Thanks!


In Mechanicals | Asked By Arthur Ledoux | Nov 3 15
5 Answers

What is a good R-factor estimate for a wall assembly with old UFFI foam from the 1970s?

I'm doing some modeling to guide a DER of a 1900's house. Bore-and-fill urea/formaldehyde insulation was added in the 70's. It's shrunk a bit and is quite fragile as expected. I'm looking for a realistic R value to use for this assembly. The wall is 2x4, plaster and lathe on the inside, 2 layers of siding on the outside. My guess is that the old foam has an R of 12 total (3" at R4 per inch). Any inputs on what R to use for this assembly?



In General questions | Asked By Tom Lange | Nov 5 15
2 Answers

Vapor barrior termination on mono slab?


I am building a small house in TN on a mono slab. My local building inspector strongly recommends not insulating the sides of slabs due to termites in my area. So, my question is where should I stop the vapor barrier? See attached pic. My initial thought was to stop at point C, but if there is any incorrect sloping I would think water could get trapped between points C and B. Should I stop it at point B?

I very much appreciate any thoughts on this.


In General questions | Asked By JOE ROBERTS | Nov 3 15
15 Answers

ERV vs. positive pressure vs. none

Leaky 1800's log home. Radon issue being worked on via traditional methods with mixed success. Radon issue improves dramatically when windows are open -- I assume this is dilution and perhaps also pressure equalization?

Wondering if ventilating may help dilute radon w/o the windows open energy penalty, especially in winter. If so:

1. Positive Pressure Ventilation -- perhaps a dehumidifier ducted to draw outside air -- might the positive pressure help reduce radon draw and simultaneously dilute the radon issue?

In Mechanicals | Asked By Andrew S | Nov 3 15
1 Answer

Spinning of washing machine

i have not choosen the spin mode while starting the washing machine after washing is completed,water has driven out while removing the door ,is spin is manadatory in front loaded washing machine,my brand is samsung front loaded machine please reply to my mail bhargavraj091@gmail.com

In General questions | Asked By Bhargav Pichika | Nov 5 15
3 Answers

Suggestions for insulating a 1770s New England church building

A local First Congregational Church (Climate zone 5) , established in 1770, is looking to use their building year round. Typically, it is too cold to use in the winter months due to no insulation and excessive heating bills.

In Energy efficiency and durability | Asked By Jon Michael Wyman | Nov 4 15
15 Answers

Non-standard low slope roof -- best way to insulate and ventilate?

I am trying to find a solution to properly insulate and ventilate an attic in my house. We purchased the house two years ago. The house had a history of ice dams. Before the first winter in the house, based on recommendation from the energy auditor, we had the house air sealed, added cellulose to the attic and additional vents in the roof (turtle vents) installed. Unfortunately, it did not help and with all the recent snow we are dealing with now (Boston area) there is another ice dam damage. The temp. in the attic is 40F when the outside temp is 20F.

In Energy efficiency and durability | Asked By Marcin Nowak | Feb 10 15
1 Answer

Crawl space

We are getting ready to build a fairly large addition on a house that has a crawl space. We are bumping out the back of the house and the grade rises gradually. In order to maintain a reasonable height in the new crawl,we would need to have the interior elevation lower than the exterior. We would plan on installing a curtain drain in conjunction with a french drain linked to a sump pump. I have suggested to the client to encapsulate both crawl spaces but he is extremely reluctant.

In Energy efficiency and durability | Asked By Mike Labesky | Nov 4 15
4 Answers

Larsen Truss vs. Joe Lstiburek's Ideal Double-Stud Wall Design

I'm designing a house for Rochester, NY, zone 5. It's going to be a single floor with a finished basement. The roof will be constructed with raised heel trusses and insulated with cellulose. I don't want air-tight drywall, so I'm planning on using a layer of plywood or osb to form the ceiling air barrier.

In Green building techniques | Asked By John Ranson | Nov 1 15
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