Need advise - securing a pergola to patio
#1
Member
Thread Starter
Need advise - securing a pergola to patio
Greetings,
I need to secure a 10'X12' pergola/gazebo to a concrete patio. Each of the four pergola's legs has a plate with 4 holes in it and I was thinking of using Tapcon screws.
I never used this screws before. Are there any specifics I need to be aware of before doing it? What length of screw would you use?
How far do I need to be from the patio's edge (is there a chance the slab could crack while I drive the screw down?
Shall I also use construction adhesive underneath the 4 plates or is this an overkill?
Appreciate any advice.
Thanks.
I need to secure a 10'X12' pergola/gazebo to a concrete patio. Each of the four pergola's legs has a plate with 4 holes in it and I was thinking of using Tapcon screws.
I never used this screws before. Are there any specifics I need to be aware of before doing it? What length of screw would you use?
How far do I need to be from the patio's edge (is there a chance the slab could crack while I drive the screw down?
Shall I also use construction adhesive underneath the 4 plates or is this an overkill?
Appreciate any advice.
Thanks.
#2
Group Moderator
I would NOT use any adhesive under the feet. In the future when the gazebo is gone you won't be cursing glue patches on your patio.
I prefer to use expansion type anchors over Tapcon's. I've had less than perfect results with Tapcon's and have had the head sheer off a good number during installation. For expansion anchors I drill all the way through the concrete slab. Your anchors don't need a hole that deep but if you get rid of the gazebo all you have to do to get rid of all those studs sticking up is hammer them down into the slab until they are flush. You can also use a nail or punch and drive them down deeper and patch the holes.
Make your holes as far from the edge as possible. I generally like to stay 4" away but have done closer. For holes closer to the edge I gently snug the expansion anchor bolts but I don't fully tighten, hoping to minimize the expansion of the fastener. If your holes need to be close to the edge I'd use epoxy and glue in your anchors so there's no force trying to crack your concrete.
I prefer to use expansion type anchors over Tapcon's. I've had less than perfect results with Tapcon's and have had the head sheer off a good number during installation. For expansion anchors I drill all the way through the concrete slab. Your anchors don't need a hole that deep but if you get rid of the gazebo all you have to do to get rid of all those studs sticking up is hammer them down into the slab until they are flush. You can also use a nail or punch and drive them down deeper and patch the holes.
Make your holes as far from the edge as possible. I generally like to stay 4" away but have done closer. For holes closer to the edge I gently snug the expansion anchor bolts but I don't fully tighten, hoping to minimize the expansion of the fastener. If your holes need to be close to the edge I'd use epoxy and glue in your anchors so there's no force trying to crack your concrete.
#3
tap cons are light duty so agree with PD that you need some type of concrete anchor to secure.
Expansion or friction type are best, glue does nothing!
Expansion or friction type are best, glue does nothing!
#4
You need to use a minimum of 1/2" drop anchor. If your post brackets do not have one big hole in the bottom center, exchange them for ones that do. You only use one anchor in the dead center. The stand off base goes on next, then you post sets on that. Then the post gets nailed or screwed through the holes provided. Use every hole.
#5
Member
Thread Starter
Thank you all.
@XSleeper - I can't chose what kind of bracket I use, this is a kit, it comes with everything. The only bracket that comes with it has 4 holes, one in each corner, and that's what I am supposed to use to anchor it.
@XSleeper - I can't chose what kind of bracket I use, this is a kit, it comes with everything. The only bracket that comes with it has 4 holes, one in each corner, and that's what I am supposed to use to anchor it.
#7
Member
Thread Starter
Don't have it yet, but this is what I'm getting and this is the manual
The image below is from the manual, the closest online image I was able to find. It comes with stakes to secure it to the ground which I clearly won't use.
The column width is around 4" wide.
I'll try to stop by Lowe's later today to measure the holes in the plate.
The image below is from the manual, the closest online image I was able to find. It comes with stakes to secure it to the ground which I clearly won't use.
The column width is around 4" wide.
I'll try to stop by Lowe's later today to measure the holes in the plate.
#8
Ah, I see. I once installed a carport style patio cover with brackets like that. A thunderstorm storm yanked it right off and blew it over the house like a kite. Reinstalled a new one... did the same thing a couple years later. Wasn't designed for that kind of wind speed and uplift.
The tapcons are probably fine... be sure you use 1/4" hex head. 1 1/4" is probably the best length. You may not be able to drive the 1 3/4" all the way in. The weak point in that design is the nearness of the column bolts to the bottom edge of the metal. That will rip out before the tapcons do. And the tent stakes are the only thing that will keep it from shaking the roof in a storm. The shaking is what will fatigue the metal at the column base. Without the tent stakes there isn't much to keep it square and plumb.
The tapcons are probably fine... be sure you use 1/4" hex head. 1 1/4" is probably the best length. You may not be able to drive the 1 3/4" all the way in. The weak point in that design is the nearness of the column bolts to the bottom edge of the metal. That will rip out before the tapcons do. And the tent stakes are the only thing that will keep it from shaking the roof in a storm. The shaking is what will fatigue the metal at the column base. Without the tent stakes there isn't much to keep it square and plumb.
#9
Member
Thread Starter
The stakes are not tent stakes, they are short stakes that you're supposed to use in the bottom plate to secure it to the ground/soil. They are not meant to hold the canopy.
#10
Ahh, I see. Well, none the less... I bet it will shake in the wind. I retract what I said about the 1/2" anchors... your tapcons should be fine as long as they are drilled and driven well. (Holes aren't rounded and screws don't spin.)
#11
Member
Thread Starter
So I brackets at the store. The holes in the brackets can accommodate screws up to 5/16" (I actually took a 5/16" Tapcon and it's a perfect fit).
I also don't know what length I'll need, I am not at the house and don't know what the thickness of the patio is.
I am not sure though why are the 5/16" flat at the bottom and the 1/4" for example have a point head.
I also don't know what length I'll need, I am not at the house and don't know what the thickness of the patio is.
I am not sure though why are the 5/16" flat at the bottom and the 1/4" for example have a point head.
#12
Group Moderator
Go 1 1/2" at most and better might be 1 1/4'. The longer the screw the greater the chance you'll wring the head off installing it.
#13
Member
Thread Starter
So looks like that the 5/16" Tapcon are the heavy duty ones (with flat bottom) and the shortest one is 2 1/4". I'll have to go with the 1/4".