Insulation for shop ceiling

tman1020 · Dec 10, 2015

Got the furnace mounted and fired it up this morning it works fantastic. Looks different sticking way up in the air like that but I like it. I'm going to put my toolbox right underneath it so when the furnace kicks on it will blow warm air on my tools to keep them warm. That way when I'm out there and have to use handtools they wont be freezing cold. It was 45° this morning when I fired it up I Ran it for about half hour straight and it was up to 55° and I have no insulation in the ceiling yet. I think it's going to work out very nice.

gsganzer · Dec 10, 2015

tman1020 said:
View attachment 449966

Got the furnace mounted and fired it up this morning it works fantastic.

Cool! Is that just a regular furnace like you typically have mounted in a closet in your house as part of a forced air system? I never thought of using an old one like that for heating a shop. Brilliant!

ovrszd · Dec 10, 2015

I use a house furnace to heat my shop when I'm too lazy to fire up the wood stove.

I studied that picture closely and can't figure out what that furnace is??? I'm guessing by your comments that it blows out the bottom?? You aren't gonna want your tool box under it, unless you like hot tools. 45 degree outside temp is not a test of your furnace. When it's really cold out and the furnace runs for 30 minutes without shutting off you'll see what I mean.

You are gaining. It'll all come together after you use your shop awhile.

Just understand, you can't heat a building without insulation. You can only take the chill off.

tman1020 · Dec 10, 2015

Yes it's a 80% down draft that a friend that runs a HVAC shop saved for me. Someones ac went out and they just decided to replace the whole system so I got the furnace, it seems to be in very nice shape. I'm hoping to have the ceiling insulated by next week but it was nice to run the furnace while I was working in there just to take the chill off and the dampness out this morning. I don't think hot tools will be a problem. You can stand right under it and it's nice and warm but not hot. I think the fan blows high enough CFM to prevent getting to hot. Im more worried about condensation on them. It sure is better than the torpedo heater I was using. Man that thing was loud and annoying. If all goes well I should finish up the walls tomorrow if I don't get called away.

ovrszd · Dec 11, 2015

Your tools will only condense if they are hotter than the shop air.

tman1020 · Dec 18, 2015

Got it started.

GPintheMitten · Dec 18, 2015

tman1020 said:
View attachment 450919

Got it started.

Great. It's going to be nice to have heat and insulation.

Do you have an air gap above the insulation to allow ventilation?

ovrszd · Dec 18, 2015

Looking good!!!!

If you haven't bought all of the insulation yet, I'd suggest buying rolls rather than pre-cut bats. Minimizes the splices you'll have. Be very, very diligent about leaving any gaps, even the smallest gaps.

As for ventilation. If the insulation stays up against the roofing you'll be okay. If it sags and creates air gaps between the insulation and sheeting then you'll have a problem. Can't tell for sure, but hopefully your insulation is thicker than your rafters?? If so sheeting under it will press it tight against the sheeting.

tman1020 · Dec 18, 2015

I have a full vented attic above. I am buying rolls not batts. I'm just cutting up to the middle where I have some osb laid for storage i'm using R19 everywhere except for under the osb storage area which I will use R13 there. It was 30° here yesterday and I had about half the ceiling done. Before I turned on the heat it was 10° warmer in the building. It's 28° outside here now and I have my furnace set at 54 and it is cycling on and off even with a very large portion not insulated yet. It was kind of cool yesterday when I walked in as I walked right past the line where I had stopped insulating it was colder. Kind of like walking into a wall of colder air. I will try to be mindful of any and all air gaps. I'm not planning on heating this building all the time just on occasion when I need to work out there but who knows what the future holds. I figure I could always add more over the top of this if need be. But it is pretty Nice having a place that I can get warmer to work and I'm sure I'll use it more than I think now that I will have it.

tman1020 · Dec 28, 2015

Well I just finished insulating the ceiling in the shop. What a huge difference. So far it has consistently stayed about 10° warmer in there without running the heater. When I do use the heater it heats up very quickly and holds the heat very well. Much nicer than my old kerosene torpedo heater. I thought I'd post this picture of another idea I came up with. I have a fan from an old furnace that I tore out that I had recently replaced the motor in. I mounted the fan in the ceiling of the barn to act as a ventilation fan. As I have it set up it should suck air out of the barn and push it into the attic. I thought this would be handy on hot days. I'm thinking it will draw hot air from the ceiling and push it into the attic and that should force some of the hotter air allready in the attic out the vents.