Proper method to install tie down anchors on roof?

Drilling through Eternabond tape will encapsulate the screw head and seal the hole.

I hope their video works. It shows the screw driven through the tape and an aluminum trim piece.

I might even think about VHB tape and then sealant if I was doing this.

If you use self tapping screws you won't need to drill a hole. Just put the right bit in your drill motor and drive the screws right into the wood. I just showed that bit so you can see what I mean. Those roofing screws are hex headed and you drive them with a bit like that. Your local hardware store will sell them individually so you can get one the right size. They are often 5/16" but not always.

I'd mark the screw hole locations. Start the screws--drive them in maybe a 1/4 inch and remove the screws. Coat the bottom of the cleat with Dicor, position it over the holes and then drive the screws all the way in. That should seal the cleat.

The reason for doing it this way is that the cleat may be hard to control, that is will be slippery, with the sealant on it. So pre-drilling the hole part way prevents that from being a problem. The screw inserted into the hole will control the location of the cleat. Not putting the screw all the way in gives you the tightest possible fit in the hole it creates. Do not over drive the screws that will ream out the hole and give you a poor fit.

Thinking about it I would use 1 inch long screws max, since I don't know how thick that roof is. Using these roofing screws you won't have to worry about them corroding. They are coated and designed to exposed to weather. Stainless screws are weaker and you have to worry about wringing the head off the screw when you drive them.

agesilaus wrote:
Link to cleats: ***Link Removed***

You would want to use Dicor sealant under the cleats: ***Link Removed***

I'd use the largest self tapping screw that fits into the holes on the cleats. Maybe 1 1/2" long but you don't want to go thru the roof so that may be too long. Something like this: ***Link Removed***

However my concern is just what do you plan to carry up there, how much does it weigh. That roof is not designed to be load bearing. And I have my doubts about how strong those cleats will be. Don't forget you are going to have the wind load to deal with besides the weight of whatever you carry. At 60 mph that wind load can be substantial.

If I was installing them on a boat I would drill thru the roof and put a metal backing plate in on the ceiling side with machine screws passing thru the roof. Not practical in this case.

The anchors will not be used to carry heavy weights, only to hang tarp off the side, it just has to handle high gusts of wind - that's why I can't use the awning.

thank you for the suggestions.

A followup question: Regarding the Dicor sealant under the cleat, just to clarify, you recommend I lay down the sealant, place the cleat on top of sealant, then drill the holes through the sealant, correct? Do I wait for everything to dry first? Should I apply more sealant after the screws have been drilled through?

don't put anything valuable in whatever you put on the roof. as stated, that wind will eventually loosen the screws.
bumpy

Link to cleats: Amazon

You would want to use Dicor sealant under the cleats: Dicor

I'd use the largest self tapping screw that fits into the holes on the cleats. Maybe 1 1/2" long but you don't want to go thru the roof so that may be too long. Something like this: Screw

However my concern is just what do you plan to carry up there, how much does it weigh. That roof is not designed to be load bearing. And I have my doubts about how strong those cleats will be. Don't forget you are going to have the wind load to deal with besides the weight of whatever you carry. At 60 mph that wind load can be substantial.

If I was installing them on a boat I would drill thru the roof and put a metal backing plate in on the ceiling side with machine screws passing thru the roof. Not practical in this case.