ECN Forum Forums General Topics of the Trade General Discussion Area plastic anchors in ceilings?

Can plastic anchors be used in concrete ceilings for hanging light fixtures?

No.

I think it would come down to who is inspecting the job and the local rules. Holding pipe up with plastic ancors is not permitted in some areas also.

If there is a fire I don't think it would not take much heat for the ancor to melt and what ever to fall.

Inspectors are concerned about things falling on fire victoms and fire fighters.

I have not seen any kind of overhead rating for plastic ancors as I beleve they are ment for more of a shere force.

Tom

Plastic anchors, like any other anchor, have specified pull-out and shear strengths. While it would have a much greater shear strength than pull-out, plastic anchors have been used for years to hold light weight fixtures to ceilings. If weight is a problem, switch to lead anchors or some other metal shield.
As to melting under fire conditions, it would have to first heat up the concrete to melt the plastic. At those temperatures, I don't think it would matter.

Earl

Well, after finding out that the zinc alloy nail-in anchors are not supposed to be used for anchoring to ceilings (because of the low fusing tmeperature), it just made sense to me to have the same prohibition for plastic anchors. Yet, I haven't found any literature to that effect. Recently I removed some stem hung 2 tube 8 ft fixtures, and they were fastened to the concrete with plastic anchors, and it just seemed too flimsy, especially because of the increased dynamic load due to the 3 ft long stems.

use tapcon's you have to drill a hole anyway

Lead anchors are illegal in my area now for years, they've been replaced with steal. There's gripple, they make several different types of hanging systems for fixtures. They have a website. www.gripple.com
check them out.

~Andy

How about shooting in 1.5 nails? HILTI or RMINGTON power guns.

Edward

I've been told by different inspectors they can't be used as well as lead can't be used for those same reasons. In case of fire for the protection of victims as well as fire fighters. I would think that with enough convection, but I'm thinking moreso enough radiant heat that it would conduct rather easily through whatever was being fastened, down the shank of the screw, and turn it to liquid.

I like tapcons myself.

Has anyone actually done tests on these different fasteners in a controlled (fire)environment before passing judgement? I would tend towards Earl's opinion that if the concrete has got that hot then no-one is passing underneath.