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Matt Findley Posted: Jan 05, 2007 04:41 PM	High rafters.Spray drywall ceiling? I'm new to this and have a new home coming up that has high ceilings and rafters. We will be unable to get to the roof decking in some areas. I want to make sure it is done correctly. So, can I spray on top of the drywall ceiling? What do I do about the can lights? Do I need to make a box around the can lights before spraying or cover them somehow? Any information would be helpful. Thanks in advance.
Dave Strnad Posted: Jan 05, 2007 05:51 PM	Yes you can spray on top of the drywall. As far as can lights, if they are approved for direct bury than you can spray over them. However I would caution against this. I've done it before and the lights will nusince trip the temp breaker, very annoying. I have wraped in fiberglass and sprayed over that, which seems to work better.
Gerry Wagoner Posted: Jan 07, 2007 10:15 AM	You can spray over IC lights. I've done it on our own can lights in the master bedroom.
Matt Findley Posted: Jan 09, 2007 07:58 PM	Did you use open or closed cell? Thanks.
Posted: Jan 09, 2007 08:14 PM	just looked at a job today with can lights. I will be spraying down onto the drywall up in the attic. can light has holes in the side. sticker on top says to keep a 2" clearance on sides. wrap it up in fiberglass and and spray it with foam? won't get too warm? Is this the same type of light you sprayed George?
Glenn Gamblin Posted: Jan 13, 2007 07:18 PM	Never ever spray can lights with foam. It isn't worth it. You can spray a strip of foam on plastic and roll it up to make a circle before it sets up. you then spray another spot on the plastic to put on top of the circle. It will look like a circus hat if done correctly. You then place it on top of the can light and foam it in. cardboard boxes also work if you can find them.
SprayFoamSupply.com Posted: Jan 14, 2007 07:55 AM	I did a similar thing Friday over some can lights. I was spraying open cell down onto the drywall. I sprayed a circle down around the can light, then another pass, making a donut around the light. 3 passes and I was about 2" taller than the light. I then placed a scrap of drywall on the donut and foamed it in. I am confident that I had at least 2-3" of air space around the can. I then made sure I had 8" over the top. It worked great on the bathroom fanlight too. Spraying down on the drywall with OC is cost effective for the homeowner. This job had trusses with a 2x4 bottom chord. We sprayed over that which eliminated much of the thermal bridging. I have some pics if anyone wants them, email me. George
Posted: Jan 14, 2007 11:11 AM	insulation bury-able cans are ok to bury with foam.. i cover/wrap mine with a glass cap...and seal/cover it...the electricians like the idea too... have used buckets,,drywall scrap boxes,,rose cones..cardboard boxes,,,they all worked... i use the glass as its fast and furious,,, and it is easy to have the required material on hand in the trailer... time is money.. ps: watch out for the "stairwell wall light" fixtures (typically a white metal box with fixture inside)these are not meant to be insulated over/around and will thermal trip if you foam over em...disco stairwell,,,cool...
Brian Ahrens Posted: Jan 14, 2007 06:08 PM	Make sure there is one coat of mud on the ceiling or you will be in for a big surprise when you climb down. I have tried them all, rose cones work great for speakers and when more than 20 can lights we make boxes out of 1 inch polystyerene and assemble them with nails. It is fast once you get the tablesaw set up to the dimensions you need. We also found that the cardboard baffels made to fit 24 o.c. rafters are a huge time saver just point and spray.
Matt Findley Posted: Jan 15, 2007 09:52 PM	Thanks a lot for the info. I will be trying it soon. Some pics would be great!

Author

Comments

Matt Findley

Posted: Jan 05, 2007 04:41 PM

High rafters.Spray drywall ceiling?

I'm new to this and have a new home coming up that has high ceilings and rafters. We will be unable to get to the roof decking in some areas. I want to make sure it is done correctly.

So, can I spray on top of the drywall ceiling?

What do I do about the can lights? Do I need to make a box around the can lights before spraying or cover them somehow?

Any information would be helpful. Thanks in advance.

Dave Strnad

Posted: Jan 05, 2007 05:51 PM

Yes you can spray on top of the drywall. As far as can lights, if they are approved for direct bury than you can spray over them. However I would caution against this. I've done it before and the lights will nusince trip the temp breaker, very annoying. I have wraped in fiberglass and sprayed over that, which seems to work better.

Gerry Wagoner

Posted: Jan 07, 2007 10:15 AM

You can spray over IC lights. I've done it on our own can lights in the master bedroom.

Matt Findley

Posted: Jan 09, 2007 07:58 PM

Did you use open or closed cell?

Thanks.

Posted: Jan 09, 2007 08:14 PM

just looked at a job today with can lights. I will be spraying down onto the drywall up in the attic. can light has holes in the side. sticker on top says to keep a 2" clearance on sides.
wrap it up in fiberglass and and spray it with foam? won't get too warm?
Is this the same type of light you sprayed George?

Glenn Gamblin

Posted: Jan 13, 2007 07:18 PM

Never ever spray can lights with foam. It isn't worth it. You can spray a strip of foam on plastic and roll it up to make a circle before it sets up. you then spray another spot on the plastic to put on top of the circle. It will look like a circus hat if done correctly. You then place it on top of the can light and foam it in. cardboard boxes also work if you can find them.

SprayFoamSupply.com

Posted: Jan 14, 2007 07:55 AM

I did a similar thing Friday over some can lights. I was spraying open cell down onto the drywall. I sprayed a circle down around the can light, then another pass, making a donut around the light. 3 passes and I was about 2" taller than the light. I then placed a scrap of drywall on the donut and foamed it in. I am confident that I had at least 2-3" of air space around the can. I then made sure I had 8" over the top. It worked great on the bathroom fanlight too. Spraying down on the drywall with OC is cost effective for the homeowner. This job had trusses with a 2x4 bottom chord. We sprayed over that which eliminated much of the thermal bridging. I have some pics if anyone wants them, email me.

George

Posted: Jan 14, 2007 11:11 AM

insulation bury-able cans are ok to bury with foam..
i cover/wrap mine with a glass cap...and seal/cover it...the electricians like the idea too...
have used buckets,,drywall scrap boxes,,rose cones..cardboard boxes,,,they all worked...
i use the glass as its fast and furious,,,
and it is easy to have the required material on hand in the trailer...
time is money..

ps: watch out for the "stairwell wall light" fixtures (typically a white metal box with fixture inside)these are not meant to be insulated over/around and will thermal trip if you foam over em...disco stairwell,,,cool...

Brian Ahrens

Posted: Jan 14, 2007 06:08 PM

Make sure there is one coat of mud on the ceiling or you will be in for a big surprise when you climb down. I have tried them all, rose cones work great for speakers and when more than 20 can lights we make boxes out of 1 inch polystyerene and assemble them with nails. It is fast once you get the tablesaw set up to the dimensions you need. We also found that the cardboard baffels made to fit 24 o.c. rafters are a huge time saver just point and spray.

Matt Findley

Posted: Jan 15, 2007 09:52 PM

Thanks a lot for the info. I will be trying it soon. Some pics would be great!

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