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Expanding bolts in brick wall to attach pergola?

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Chris152

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I have 5 x 10mm expansion bolts that expand into 15mm holes, to attach a plate above my patio doors (38mm x 75mm x 2.6m) into brick. Onto the plate I'll be attaching eight cross beams of a pergola (well, sort of - it's more a frame for a vine to grow across, looking like a pergola), each beam about 2.5m long and same dims as the one attached to the house. I already have in place the uprights and beam for the opposite end of the pergola.

Am I ok to attach the bolts into the bricks, approx 1/3 up from the bottom of the bricks to avoid the voids in the bricks? I know not to over-tighten. Or am I better using concrete screws (which I also have), since it's not going to be holding a lot of weight?

Thanks for any advice,
Chris
 

Rorschach

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I'd probably use frame fixings myself, very good for outdoor purposes as the plastic plug goes through the wood. Nice strong fixing, cheap and easy to install.
 

MikeG.

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There are bricks and bricks, Chris. In some types I'd say crack on with the expansion bolts if that's what you have to hand (they seem like a massive overkill from what you've described). In some others I'd do that short intake of breathe between the teeth.....you know, the one the builder does just before the price doubles. Ideally, I'd suggest frame fixings, but if that's too much of a complication you'd best stick a photo or two of your bricks on here and we'll see if any of us recognise them.
 

Chris152

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MikeG.":3ge751op said:
they seem like a massive overkill from what you've described
It's what you do when you don't know what you're doing, but know you don't want it all falling on someone's head! :) Point taken, expansion bolts (and newly purchased 15mm masonry bit) back in the shed - wish I'd asked this question earlier.
I'd not heard of frame fixings before you mentioned them, Rorschach.
Should I go for 8 x 80mm or 10 x 100mm - screwfix and toolstation specify the diameter of the plug but not the screw? They look easier to fit than the bolts so I can use more if that's going to be better.

Btw - these are the bricks, dating from 1970 - my guess is they are cheap and brittle, and hollow.
IMG_20200502_162828.jpg
 

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Rorschach

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Do the frame fixings have specs on them? As a rule of thumb I go for about 2" into the wall so you might struggle with 75mm timber. You could use brown plugs doubled up and suitable length screws, 120mm would that be, I can't remember the length of a brown plug off the top of my head?
 

Chris152

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The timber's 38mm thick (75mm tall) so 10 x 100mm will give 60+mm in the wall - maybe 8 x 80mm is the one to go for. But diameter of the screw itself they don't seem to specify.
 

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I would be very surprised if those bricks were hollow.
I take it youre going to run wood along the wall?
have a look at my pergola build thread. I used rawl bolts to hang joist hangers . If youre not going to put a roof and tiles on it then theres no worry about either method collapsing. Mine has something like a metric tonne of clay tiles.

https://pbase.com/john_cooper/bob_coopers_pergola_extn
 

Rorschach

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Chris152":3n54r3i3 said:
The timber's 38mm thick (75mm tall) so 10 x 100mm will give 60+mm in the wall - maybe 8 x 80mm is the one to go for. But diameter of the screw itself they don't seem to specify.
Ah ok in that case yes 80mm will be fine. The screw will be about 5mm thick but on frame fixings the plug stays in the wood so you will need to drill an 8mm hole through the wood and the masonry.
 

Chris152

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That's great - thanks fellas.

SB - that's the kind of thing I originally wanted, it looks great. I might go for a small sheet of solid polycarbonate (about 50cm x 100cm) directly above the door, just to stop rain coming in when doors are open in summer, but no real weight in that.

I'll post a pic of mine once the vine's grown sufficiently that you can't see the woodwork. :)
 

sunnybob

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Strangely, I dont like the fischer type screws because they just dont "look" strong enough to hold stuff up above my head. I've used rawl bolts since they were invented (I think) and never had one fail. The secret is to drill the correct sized hole and fully insert the bolt .
Out here there are many vine shaded pergolas, most of them built with galvanised water pipes and stainless wire.. :shock:

A word of warning about vines growing around the doorways.... They attract huge quantities of flies. If that door is usually left open youre going to want to build a fly screen next. :roll: =D> 8)
 

Woody2Shoes

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sunnybob":1vilucwa said:
Strangely, I dont like the fischer type screws because they just dont "look" strong enough to hold stuff up above my head. I've used rawl bolts since they were invented (I think) and never had one fail. The secret is to drill the correct sized hole and fully insert the bolt .
Out here there are many vine shaded pergolas, most of them built with galvanised water pipes and stainless wire.. :shock:

A word of warning about vines growing around the doorways.... They attract huge quantities of flies. If that door is usually left open youre going to want to build a fly screen next. :roll: =D> 8)
I agree about the frame fixings - most of them are relatively thin, and pullout strength increases markedly as the diameter of a fixing goes up, all things being equal - also I quite often shear the head off as I do them up. I think that success with the expanding rawlbolt does depend on the consistency of the substrate - and having a way of getting all the dust out of the hole without getting it in your face :lol: .
 

Phil Pascoe

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I prefer to use resin studs or Thunderbolts rather than frame fixings or Rawlbolts for jobs like this as they are easier to adjust when things don't go quite to plan.
 

Chris152

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Woody2Shoes":12ii22ay said:
I agree about the frame fixings - most of them are relatively thin, and pullout strength increases markedly as the diameter of a fixing goes up, all things being equal - also I quite often shear the head off as I do them up.
According to this link, you hammer rather than screw them in?
https://www.youtube.com/watch?v=8NIUfORnK8g (about 4'40" in)
 

Lons

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Chris152":2iht914y said:
Woody2Shoes":2iht914y said:
I agree about the frame fixings - most of them are relatively thin, and pullout strength increases markedly as the diameter of a fixing goes up, all things being equal - also I quite often shear the head off as I do them up.
According to this link, you hammer rather than screw them in?
https://www.youtube.com/watch?v=8NIUfORnK8g (about 4'40" in)
I haven't watched the link yet Chris but there's a difference between hammer fixings and frame fixings.

I've used a lot of both types over the years and still have a sizeable stock as I bought them by the 100s in various sizes. Hammer fixings are surprisingly strong especially if the load is down rather the pull horizontal and they are very quick and easy to fix, the only thing to be careful of is that ideally the hole through the timber should be fractionally larger than that in the masonary or the plastic plug can bend as you tap it through and you wreck it pulling back out, also once knocked home a nip up with a screwdriver doesn't hurt and you can actually screw them back out though the plug stays put. 80s and 100s were the most used though I've also got some 120s and I've never had anything fall down or pull away in 25 years.

Frame fixings I used mostly on window and door frames because easier to adjust but I never felt the hold any better then hammer fix. Toolstation were cheaper than Scewfix btw though don't know if it's still the case, unfortunately they've just increased free delivery order from £10 to £25. :(

I'm of the same opinion as Mike however as the brick should be fine with expanding bolts or epoxy studs both of which are probably overkill but you already have them!
 

Chris152

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Lons":192wejxj said:
there's a difference between hammer fixings and frame fixings.
Aha!

I'm tempted to go ahead with the expansion bolts as I have them and want to avoid going shopping, and if I use something else (other than the concrete screws I already have) I'll have to wait till they're delivered. Problem is I'd be doing it on my own and making sure the holes into the brickwork are in the right place is harder with the bolts as those holes need to be bigger - I think the hammer fixings with a wait are looking most likely, as I can get the centre one in and do the others relatively easily.
 

Rorschach

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I'll put the case for frame fixings over rawlbolts or similar.

Rawlbolts (expanding bolts) are expensive, especially if you need to fix thick items, thin items like TV brackets are cheaper. If you mess up the hole on the rawlbolt it is difficult if not impossible to remove and sometimes you don't realise the hole is bad until you have tightened (and ruined) the rawlbolt and it just keeps spinning in the hole but you still can't remove it.
They are super strong though and in the right application are superb.

Frame fixings are cheap, very easy to install. Somewhat forgiving of hole size. You know right away if you have a good fix or not and if you don't have a good fix you can remove them really easily. Even if the plastic plug gets stuck you can drill it out in seconds. Because the hole for a frame fixing is fairly small, if you do drill oversize you can easily step up to a bigger fixing or stronger fixing if required. Once you drill the massive hole for a rawlbolt there is no going back really.

I don't mind whether I use hammer or screw in frame fixings, the hammer are faster if you are doing hundreds maybe but most of the time I am doing just a handful so screwing them in barely adds any time. Both types are easy to remove I have found.
 
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