New Shop instulation question.

[Chad S Young]

I am in the process of building a new 34X48X14 shop. I do some wood working but more general farm repairs. I am looking at having the closed cell spray foam installed and painted. I was wondering if it is much trouble to keep clean from all the sawdust or would I be better off to leave it out of the shop. Located in Texas so it does get hot but most of my work is in the evenings.

[Jim Becker]

Properly applied closed cell spray foam isn't going to catch dust any more than any other material you might use. IE, no matter what you use, there will be some accumulation of dust if dusty activities are done. There's really no need to paint the spray foam as it's almost always a light, neutral color ranging from yellowish white to very light green, depending on the manufacturer and formula. It's almost always fire-retardant and can be left exposed, too, unlike fiberglass products. It will stiffen your structure substantially and is a great air and moisture barrier, too.

For practical reasons, you'll want to clad the walls to above working height with something to provide physical protection, however. Plywood or steel is typical for that purpose in buildings like this and is usually installed vertically over girts for a post-frame/poll-barn type structure.

[Erik Loza]

Chad, I would definitely go the spray-in foam option. I have a local (Austin area) customer who just did a shop similar in size to yours and it came out really nice. Also quiets everything down. Regarding dust, I have been in a million shops and the real answer depends on how good your DC system is. There's always a little but if the machines are well ducted and the DC is up to par, doubtful you will get enough accumulation on the walls and ceiling to worry about. Hope this helps,

Erik

[Chad S Young]

My dust collection is currently zero. Ill probably add some but my tools have been in storage for 12 years. I cant wait to get started again. Just teyimg to decide if it is worth 4600 or just leave the walls alone. Thanks.

[Jim Becker]

Even if you don't actually condition the space, the insulation is going to make the building a whole lot more comfortable and make temperature swings less. Further, the spray foam will eliminate condensation on the inside of the walls when the dew point fluctuates, especially if it's steel. Erik already mentioned reduced noise.

[Ronald Blue]

I considered spray foam but went with 6" fiberglass in the sidewalls and 15"+ blown in fiberglass in the ceiling. 30x56x14 Plastic between the outer tin and the insulation. It went from deafening during a rain storm to you don't even know it's raining unless it's a torrential down pour. I lined the walls with 3/4" OSB on the bottom and white ribbed metal above. OSB is also white. The ceiling is the same white tin. Then I put in high bay LED's. It's so nice in there. About 150 CP at waist height. I know the spray foam is popular because it's usually a one day process but it was far more expensive here. I would have wanted the inside finished out the same either way. All electrical is ran in conduit on the surface. Whatever you decide good luck with it.

[Bobby Robbinett]

My dust collection is currently zero. Ill probably add some but my tools have been in storage for 12 years. I cant wait to get started again. Just teyimg to decide if it is worth 4600 or just leave the walls alone. Thanks.

If you have a spray foam company that will do your walls and roof bottom for $4,600 then I would jump on it. Here where I live just east of you it would cost upwards of $6,500 with tax included. My local guy charges $1.48 per square foot or $1.66 with tax. I looked into doing my own shop myself and I can’t even buy the tanks of spray foam for that. I want to say it was roughly $600 to $700 per 600 square foot for closed cell and that is without the gun.

I will say though that spray foam is excellent and I seriously doubt that you would ever regret doing it. If you plan to run an air conditioner then you absolutely need to do it! I have a couple of used 5 ton air conditioners in my shop and I am saving up to spray foam my shop as well because those two 5 ton a/c units will not completely cool off my 100x90 shop. My shop was originally insulated with rolls of fiberglass behind the metal but it was installed in the 1960’s I believe so most of it is no good. Especially the ceiling. My shop is an odd shaped metal building

[Jim Becker]

I considered spray foam but went with 6" fiberglass in the sidewalls and 15"+ blown in fiberglass in the ceiling. 30x56x14 Plastic between the outer tin and the insulation. It went from deafening during a rain storm to you don't even know it's raining unless it's a torrential down pour. I lined the walls with 3/4" OSB on the bottom and white ribbed metal above. OSB is also white. The ceiling is the same white tin. Then I put in high bay LED's. It's so nice in there. About 150 CP at waist height. I know the spray foam is popular because it's usually a one day process but it was far more expensive here. I would have wanted the inside finished out the same either way. All electrical is ran in conduit on the surface. Whatever you decide good luck with it.

I follow a post-frame builder on YouTube up in your neck of the woods. Most of their projects are done as you describe with R19 fiberglass in the side walls and R38 blown in over the steel ceiling, all with poly vapor barriers on the inside. Some of their buildings do get spray foam in the side walls and they seem to typically spaces that that are either residential or "higher end" applications. Lower cladding on their stuff is AC Plywood typically rather than OSB.

[Todd Mason-Darnell]

My dust collection is currently zero. Ill probably add some but my tools have been in storage for 12 years. I cant wait to get started again. Just teyimg to decide if it is worth 4600 or just leave the walls alone. Thanks.


Chad, I am just outside of Austin and if you have someone who will spray a 34 x 48 shop for $4600, I would take that deal in a heartbeat.

[Bill Dufour]

If you have exterior wainscotting it is recomended to have some tvvek or such inside to that height before spraying. That way you can remove and replace the wainscotting if you ever need to. Install the material before the sheet metal goes on.
Bil lD

[Walter Mooney]

Chad, I agree with Todd -- I'd take that deal (and smile all the way to the bank). That's a great price! There are basically two kinds or types of foam -- open cell and closed cell. Open cell is usually less expensive, and, since it's "open cell", will absorb water. It has a higher R-value per installed inch than the closed cell. However, the closed cell foam will give your new building added structural rigidity, because it dries hard, as opposed to the open cell which dries soft and almost spongy (sp?). It will be a nice pale yellow color when dry. I wouldn't paint it. I just had my little (20x20x10) new 'second' shop in the TX Hill Country sprayed with the closed cell, which I chose mainly for the added structural component.

[Erik Loza]

I'll try to post some pics later of my customer's steel building that had the spray-in done. Seriously, I would not think twice about it.

Erik

[Chad S Young]

Even if you don't actually condition the space, the insulation is going to make the building a whole lot more comfortable and make temperature swings less. Further, the spray foam will eliminate condensation on the inside of the walls when the dew point fluctuates, especially if it's steel. Erik already mentioned reduced noise.


I have decided to get the building insulated after the doors and electrical. Thanks for the feedbback.

[Chad S Young]

Thanks everyone for helping me decide to get the spray foam done. Getting the roof on today. I am excited to have a shop again after so many years. Will not be long till I can drag out the tools that I kept when I sold the last place after a divorce. Now I regret the ones I sold. Good thing is I have lots of room to buy more.

[Jim Becker]

...and, since it's "open cell", will absorb water. It has a higher R-value per installed inch than the closed cell. .

Backwards. Closed Cell has an R-Value of approximately 7.5 per inch. Open Cell has an R-Value of about 3.5 per inch. One small advantage that open cell has in a shop environment is it's slightly more sound absorbent, so some folks will do the building with closed cell for both the insulation and structural benefits and layer some open cell over that for sound abatement. Folks need to be sure about fire code, however. Most closed cell is fire retardant and can be left exposed. I haven't looked into open cell in that respect as I'd only choose closed cell personally.

----

Chad, 'glad you'll be getting back to woodworking real soon now!

[Bill Dufour]

I think you have to pay extra for them to add the fire retarder. I would think it has to be all the foam not just the top layer?
Bill D

[Jim Becker]

I think you have to pay extra for them to add the fire retarder. I would think it has to be all the foam not just the top layer?
Bill D
There was no discussion about that when our addition was done in 2008...it had to be fire retardant because it would be exposed in the attic and the crawl space...the whole structure was done with the same material. There is no real "top layer", per se...filling out a "bay" is done fast enough that it's all "one piece of foam". I guess adding more as a retrofit would create multiple "layers", however, because of time passing.

[Bill Dufour]

AFAIK rockwool is the only non flammable product that needs no additive to make it flame safe. As a teen i repacked a minibike muffler with fiberglass and watched the yellow glue burn off. Then watched threads of pure white glass float into the air.
Bil lD

[Ronald Blue]

AFAIK rockwool is the only non flammable product that needs no additive to make it flame safe. As a teen i repacked a minibike muffler with fiberglass and watched the yellow glue burn off. Then watched threads of pure white glass float into the air.
Bil lD

Fiberglass doesn't burn. If the temperature is high enough it will melt. Generally about 1000 degrees. That's the melting point of the resin binding it together. If it's melting that's the least of your worries. You have a major fire happening. It won't contribute to the fire. Your small engine exhaust gases exceeded 1000 degrees which isn't unusual.