What type of screws for attaching treated timber stud wall to masonry wall?

[Kram]

I have a dislike of SDS drill bits and generally use diamond drills for brick/masonary or concrete work. They can be harder to find in shops but amazon has them - proper brazed segment drills not the electro plated tile drill rubbish.

Then for fixings rawlplugs and wood screws are likely adequate for that. For something higher strength with fewer fixings, epoxy/chemical resin, either with threaded bar or anchor nuts.

 

[Brad93]

Why not?

You'd need to buy 100mm concrete screws to meet the nominal embedment requirement if your timber is 2x4. Fischer do sell one with a flanged washer type head for timber. Smallest they do is 8mm diameter iirc.

I'm not a fan of them in masonry. Okay for timber to a concrete pier or floor.

The cost of nylon hammer in frame fixings is much lower than a decent concrete screw.

Thunderbolts are the brand name of the masonry / concrete fixing screw I'm most familiar with.

I guess an architect / SE would look at the load, the substrate and then decide which fixing based on the requirements.

A concrete screw is going to offer higher shear strength than a nylon plug frame fixing due to the diameter and shank material. They don't exert an expansion force on the substrate which can be beneficial. They cut their threads. However this results in lower pull out strength in softer substrates.

I'm happy to ask a friend who has the right qualifications to advise if the OP likes.

 

[Dapph2]

When I battened the wall of an outbuilding I was recommended to use Fischer frame fixings. Drilled through the wood & straight into the wall in one go.

If the brick work is old and liable to split/ crumble use Fischer chemical anchoring and lengths of studding /all thread , so you get a stress free anchor in the brick .

 

[Dapph2]

The concrete screws may be better, half of the frame fixers will end up in the frog of the brick.

Bob

Not if the bricks were laid properly with the frog upwards and filled with mortar .

Saw a house locally , built 6 yrs ago by so called professional builders , do the usual upside down frog trick .
When it came to pointing up large stretches of brick runs , they had so little mortar at the edges that the pointing tool went through the mortar leaving openings along the bricks .

 

[knighty]

You'd need to buy 100mm concrete screws to meet the nominal embedment requirement if your timber is 2x4. Fischer do sell one with a flanged washer type head for timber. Smallest they do is 8mm diameter iirc.

I'm not a fan of them in masonry. Okay for timber to a concrete pier or floor.

The cost of nylon hammer in frame fixings is much lower than a decent concrete screw.

Thunderbolts are the brand name of the masonry / concrete fixing screw I'm most familiar with.

I guess an architect / SE would look at the load, the substrate and then decide which fixing based on the requirements.

A concrete screw is going to offer higher shear strength than a nylon plug frame fixing due to the diameter and shank material. They don't exert an expansion force on the substrate which can be beneficial. They cut their threads. However this results in lower pull out strength in softer substrates.

I'm happy to ask a friend who has the right qualifications to advise if the OP likes.

ah, I thought there was some weird concrete screw / wood interaction I hadn't though of

whatever he uses should only really be seeing sheer loads, and the sheer strength of anything used should be loads more than needed


I really like concrete screws, so much faster fixing up sockets / cables / whatever, used them for pretty much everything here

 

[8ob]

We had some 4x4 posts to screw to a building, supplier gave us concrete screws. I had never used them before and was a bit apprehensive, these were gate slam posts and they never budged. Sold on the idea from that day on.

Bob

 

[addjunkie]

ah, I thought there was some weird concrete screw / wood interaction I hadn't though of

whatever he uses should only really be seeing sheer loads, and the sheer strength of anything used should be loads more than needed


I really like concrete screws, so much faster fixing up sockets / cables / whatever, used them for pretty much everything here

Im a fan too, not so good into soft blocks though.

We had some 4x4 posts to screw to a building, supplier gave us concrete screws. I had never used them before and was a bit apprehensive, these were gate slam posts and they never budged. Sold on the idea from that day on.

Bob

I used them to fit the door frames in my stone storage barn. Champion, only down side is they are pricey!

 

[MetalMonkey]

This thread feels a bit like a how to get a table out of a van.
Just screw it on.

Pretty much anything will be fine, its just got to hold it in place.
If you saw how most door frames and windows were held in most properties...

Drill some holes through your timber, mark them up on your bricks, pop in some plugs and be done.
Brown plugs and some 5 or 6 mm would be fine, if you want to go overkill stick some blue plugs and some coach screws, but you will need to recess the heads with a zip drill.

If you want a one-and-done where you don't have to move the timber to put in your plugs, use some frame fixings, just don't go mad tightening them down.
Once the rest of your frame work is in place it won't be going anywhere.

 

[indykid]

This thread feels a bit like a how to get a table out of a van.
Just screw it on.

Pretty much anything will be fine, its just got to hold it in place.
If you saw how most door frames and windows were held in most properties...

Drill some holes through your timber, mark them up on your bricks, pop in some plugs and be done.
Brown plugs and some 5 or 6 mm would be fine, if you want to go overkill stick some blue plugs and some coach screws, but you will need to recess the heads with a zip drill.

If you want a one-and-done where you don't have to move the timber to put in your plugs, use some frame fixings, just don't go mad tightening them down.
Once the rest of your frame work is in place it won't be going anywhere.

I have to agree. I bet most uPVC windows are held in with expanding foam and practically structural mastic, so if you have any form of mechanical fastening, you're one up on them.

The frame fixings have the added benefit of sleeving the fastener from the treated timber, so limiting corrosion risk, not that I'd be hugely concerned either way. This thread seemed to start out assuming you had perforated bricks, but your picture shows frogs so I'm not sure the same concerns of finding voids in bricks are valid.

 

[roofman]

concrete bolts is what we use all the time..run them in fast with a 3/8 impact and bury the head into the timber.

 

[6ply]

concrete bolts is what we use all the time..run them in fast with a 3/8 impact and bury the head into the timber.

I see that's pebble dashed but I presume you'd do the same with red bricks? The ones with frogs.

 

[6ply]

I have to agree. I bet most uPVC windows are held in with expanding foam and practically structural mastic, so if you have any form of mechanical fastening, you're one up on them.

The frame fixings have the added benefit of sleeving the fastener from the treated timber, so limiting corrosion risk, not that I'd be hugely concerned either way. This thread seemed to start out assuming you had perforated bricks, but your picture shows frogs so I'm not sure the same concerns of finding voids in bricks are valid.

The frame fasteners come with wall plugs that go into the wall and not the timber being fixed to the wall, at least that is the case with the ones I have seen.

As far as I am aware the house bricks all have frogs and I assume they have been laid frog uppermost.

 

[6ply]

Rather than reply individually to every single post here yes I do agree with the general point that pretty much any fixing is going to help keep the stud work in position and when it is all in place it's not going to shift. My original post asked about the chemical interaction between some fixings and treated timber as I seemed to recall reading somewhere about using or perhaps not using a particular type of fixing with treated wood.

 

[6ply]

@roofman I presume that you are using something like this.

 

[dobbslc]

I've done loads of frame fixing in this place and for the most part I've just drilled a hole through timber and wall together and smashed a brown plug through with a 4" x 10 screw. Nothing has moved.

 

[Pigeon_Droppings2]

The deck-tite screws I used on my treated wood deck looks the same as the day they were fitted. I mostly buy exterior coated timber screws these days.

As suggested previously...resin fix and threaded bar would mean you could use fewer fixings points and it would be proper solid.

 

[Smallfry]

Fischer frame fixings. If you are worried about the screws rotting, the frame fixings isolate the screw from the timber. They are more than strong enough.

Cut the timber to length, then mark it against the wall, so the holes are in the middle (height wise) of a brick. Five each side. Spur point drill the timber first, then offer up and drill through with a masonry bit. Dewalt extreme 2 are the best. Make sure the hole id more than deep enough. BLOW OUT THE HOLE with an airline if you can. Offer up the timber and tap the frame fixings in, until the plastic plug is flush with the timber, then screw them up. Job done.

Concrete bolts are overkill for this, and I regard those torx headed screws a bit of a bodge. Window fitters use them because they are quick. They all work though, and whichever method you choose, will see you out.

With the frame fixings, only buy Fischer or Rawlplug. The cheap ones tend to have soft heads and "cam out" leaving you unable to finish getting them in, they are also more prone to snapping

 

[MattF]

My original post asked about the chemical interaction between some fixings and treated timber as I seemed to recall reading somewhere about using or perhaps not using a particular type of fixing with treated wood.

The treatment/finish applied to most, if not all, of any of these fixings should make any of them fine for the purpose. Treated wood is in everyday use by various types of tradesmen, & these are the fixings they'll be using.

 

[6ply]

Fischer frame fixings. If you are worried about the screws rotting, the frame fixings isolate the screw from the timber. They are more than strong enough.

Cut the timber to length, then mark it against the wall, so the holes are in the middle (height wise) of a brick. Five each side. Spur point drill the timber first, then offer up and drill through with a masonry bit. Dewalt extreme 2 are the best. Make sure the hole id more than deep enough. BLOW OUT THE HOLE with an airline if you can. Offer up the timber and tap the frame fixings in, until the plastic plug is flush with the timber, then screw them up. Job done.

Concrete bolts are overkill for this, and I regard those torx headed screws a bit of a bodge. Window fitters use them because they are quick. They all work though, and whichever method you choose, will see you out.

With the frame fixings, only buy Fischer or Rawlplug. The cheap ones tend to have soft heads and "cam out" leaving you unable to finish getting them in, they are also more prone to snapping

Sorry, didn't realise the frame fixing plug is set flush with the surface of the timber being fixed. I assumed it would be flush with the wall, as per a standard wall plug.

 

[Dapph2]

Hammer fix frame fixings most are talking about are like this , drill the wood then the hole with a decent sharp long SDS drill ,slip a fixing in the hole and hammer the screw head till it is a few mm from fully home then give it a tweak with a correct sized screw driver. I had the right driver bit I always in the chuck of my a heavy duty pistol drill .