Reuse Blue Board

[BuickFarmer]

Starting to consider how I want to reuse several hundred sheets of 2'X8' 1 inch thick blue board I salvaged from a chicken house I helped demolish for the tin, lumber and this insulation. Before the "eeewwwwwe, you're using chicken house materials" comments start, the bb as well as all the lumber has been sprayed down with Clorox and hosed down before storing.

My first question relates to using it on the roof. I will also be insulating the ceiling but realize the value of stopping that radiant heat as much as possible before it heats up the entire area between the roof and ceiling. Right now I am considering using it between the 2x4 purlins and nailing it to the trusses which will be on 4' centers. The purlins would need to be set 2' apart instead of 2' OC to do that but that should be no problem? Another option might be to use it over the purlins before installing the ribbed tin, but I question that it may be too flexible to screw through and into the purlins and would compromise the seal of the joints in the tin. Thoughts?

edit) the building will be 40X36X12 with a 3/12 pitch roof

 

[rieferman]

I see you're also pouring a concrete floor (from your other post) so perhaps you could consider this as under-slab insulation.

I also agree with stopping the radiant heat, but prefer a reflective barrier for that purpose.

 

[BuickFarmer]

I see you're also pouring a concrete floor (from your other post) so perhaps you could consider this as under-slab insulation.

In Georgia, would it be that effective? and would there be any concern of the the flexing boards compromising the compactive effort I put into ensuring the subgrade is at 110%. I've always wondered about that. I am only planning on pouring 4" of 3500 lb mix.

I also agree with stopping the radiant heat, but prefer a reflective barrier for that purpose.

Such as?..... bubble wrap or ???

Another option I have just thought of is to install the blue board on the bottom side of the top chord. But would have to trim around each web splice a real pita. This would in effect give a 6 inch dead air space between the tin and the bottom of the 6 inch top chord.

 

[BuickFarmer]

Question, can you glue blue board to wood?

 

[Charles (in GA)]

I see you're also pouring a concrete floor (from your other post) so perhaps you could consider this as under-slab insulation.

I also agree with stopping the radiant heat, but prefer a reflective barrier for that purpose.

In Georgia thats probably a waste. It was 25°F here last nite. I left the Used Oil Heater running, set on 55° last nite (I thought one of the cats was hiding in there, and I need to burn up some oil anyhow, I have so much) and this morning, the building (steel, insulated) was warming up (from the sunshine) so fast it outran the heater even when I bumped the Thermostat to 60° and while its only about 45° outside, the building is in the low 60's inside naturally. It will get to 50° or better outside temps by afternoon.

Typical winter day in Georgia. I think, however, we are going to see some real cold days this winter, like the winter of '10-'11.

This is the same reason radiant heat in the floor is about impossible here, with the temps up and down so much. Just look at Intellicast's 10 day forecast for Atlanta and you'll see what I mean.

Charles

 

[ilovevocs]

From a performative standpoint insulting the roof as you mentioned with the Extruded Polystyrene will certainly have a huge impact on the space, especially if it is conditioned.

You should know that the installation will likely not comply with applicable building codes. While ext. poly has a great LTTR, resistance to moisture, and a high compressive strength for board insulation its properties as it relates to fire ratings / flame spread are very poor. How does this impact you? You have to be the one to decide. Recently I insulated one of my metal buildings utilizing the ext. poly. Fabricated sheet metal cleats to hold the poly, pinned them to the girts and just snappy the insulation into place. Code compliance could likely be reached with the inclusion of type x rated gyp. into the assembly if one was so inclined.

You may be able to adhere to a wood substrate with the right adhesive, but it will have to be a water based adhesive. Any solvent based adhesive will just etch, eat, and destroy the board.

 

[BuickFarmer]

Charles, would like to hear more about your used oil heater, is there a thread on it. I have 3 ceiling electric heaters already bought and planned for use but also considered using an old Buck Stove I have had stored in the basement for years. But that's for another thread.

ilovelocs, no codes or inspections to worry about but do appreciate your input about flame spreading, had not thought about that. I plan to have a tin ceiling if that helps in that respect. I'd like to hear more about

Fabricated sheet metal cleats to hold the poly, pinned them to the girts and just snappy the insulation into place.

Got pictures?

 

[ilovevocs]

Charles, would like to hear more about your used oil heater, is there a thread on it. I have 3 ceiling electric heaters already bought and planned for use but also considered using an old Buck Stove I have had stored in the basement for years. But that's for another thread.

ilovelocs, no codes or inspections to worry about but do appreciate your input about flame spreading, had not thought about that. I plan to have a tin ceiling if that helps in that respect. I'd like to hear more about Got pictures?

The tin wouldn't have a quantifiable impact on the fire rating. Its like you said, its not a big deal, just wanted you to be aware of it in the event you pulled a permit for some interior work or something else down the road and end up surprised. I don't have pictures... I could sketch something and post it. Will do tomorrow.

 

[Krodad]

I'd attach the blue board to the bottom of the chord to give a monolithic insulating barrier using the nails with the plastic washers, then attach the tin right over that. Nothing better than that really, and will be pretty effective and tight.

Using it under the slab is not a great idea...1" of 15psi xps is good stuff, but can cause "pumping" under a floor slab. Best to stick to at least 1 1/2 or 2" of the 25psi material for that.