fixing pull up bar to cavity block house - which type of screw or bolt?

kingoffifa

as the title says i am living in a cavity block house.
i wish to fix a pull up/chin up bar to the wall but the screws and plugs that come with it are for a cavity wall. didnt think they were good enough so i went and bought some rawlbolts only to find out that the walls were cavity blocks!

i need this to be fairly secure of course so can someone tell me what type of screw or bolt i should use, and if so where can i get them.

many thanks!!

antiskeptic

kingoffifa wrote: »

as the title says i am living in a cavity block house.
i wish to fix a pull up/chin up bar to the wall but the screws and plugs that come with it are for a cavity wall. didnt think they were good enough so i went and bought some rawlbolts only to find out that the walls were cavity blocks!

i need this to be fairly secure of course so can someone tell me what type of screw or bolt i should use, and if so where can i get them.

many thanks!!

Hmm..

An effective way to tackle this type if thing is to first mount a piece of hardwood planking to the wall using a (decent) number of standard plastic rawl plugs + panel adhesive. This provides a large, firmly fixed surface area onto which you can attach your bar.

A 7"-9" wide piece of teak window board (Chadwicks) cut long enough to extend past the bars mounting plates by a couple of inches at either end would do. Window board is about 18mm thick so not too ignorant looking.

Before mounting the board, mark up/drill/countersink (c/s with a spade wood drill) holes to mount your bar to the board. The countersink allows the head of fixing bolts to sit flush with the back of the board so that it sits flat against the wall. Don't countersink more deeply than it takes to sink the bolthead/washer. 6mm diameter bolts would be sufficient


Use a large- ish diameter countersink so that you can fit penny (larger diameter) washers on the bolts. You don't want the bolt head pulling through the wood for want of a washer).

After hanging, leave 48 hours for the panel adhesive to fully harden

kingoffifa

first of all thank you very much for your lengthy reply. hopefully it will be of more use to people than just me.

i suppose if i had sent a link of the bar might have helped

http://www.argos.ie/webapp/wcs/stores/servlet/Search?storeId=10152&catalogId=13352&langId=111&searchTerms=9268434&authToken=

i get the idea of mounting a board to the wall. i had thought about that today when i saw the hager box in the garage!

i am still in shock that the house is made from cavity blocks!

i thought they were only used for crushes and garden walls!!

will let you know how i get on.

Buford T Justice

What happened when you used Rawl bolts? You could try hollow wall anchors either.

antiskeptic

kingoffifa wrote: »

first of all thank you very much for your lengthy reply. hopefully it will be of more use to people than just me.

No worries - the help I've received from folk online for all and sundry makes me want to spread the love.

i suppose if i had sent a link of the bar might have helped

http://www.argos.ie/webapp/wcs/stores/servlet/Search?storeId=10152&catalogId=13352&langId=111&searchTerms=9268434&authToken=

Ta - although it doesn't alter anything much - that bottom strut is going to be pressing against the wall so it won't take much to tie it in. If the window board was 7" wide, I'd cut 7" of it off to make a neat square. Then I'd attach it as above (with perhaps a rawlplug mount in opposite corners of the square + panel adhesive smeared evenly over the complete surface). Then bolt the bottom strut as before.

The top bracket isn't as wide as envisaged so I'd extend the board to 6" either side of it. A row of rawl plugs top and bottom perhaps 4" apart plus panel adhesive should suffice

i get the idea of mounting a board to the wall. i had thought about that today when i saw the hager box in the garage!

Hopefully the builder of your garage had that idea when he laid load spreading foundations for the cavity blocks to stand on

i am still in shock that the house is made from cavity blocks!

i thought they were only used for crushes and garden walls!!

Pretty common a method - especially in the latter part of the last century.

will let you know how i get on.

*thumbs up*. You'll get panel adhesive in Chadwicks too - It's a evostick product iirc.


(ps - if the wall has wall paper or paint on it, scratch this off before using the panel adhesive

antiskeptic

Hey Kingoffifa!

I tripped across a neat fixing this morning in my local chadwicks and it would appear ideal for your application - and a lot less involved that what I've suggested so far. I bought a couple of dozen for the toolbox

It's called a 'drop in anchor'. It works on the same principle as a rawl bolt but is only 25mm long - which means the expansion will occur in the body of the cavity block (which has a wall thickness of about 30mm) rather than in the cavity were you to use a standard rawl bolt. They cost about 20 cent a pop and I was able to buy them individually.

There's a utube video on it I've just noticed so you could check that out. Suffice to say, you want the anchor sitting in the concrete block so you need to drill deep enough to account for any plastering on the surface of the block.

Good luck whatever..

Buford T Justice

antiskeptic wrote: »

Hey Kingoffifa!

I tripped across a neat fixing this morning in my local chadwicks and it would appear ideal for your application - and a lot less involved that what I've suggested so far. I bought a couple of dozen for the toolbox

It's called a 'drop in anchor'. It works on the same principle as a rawl bolt but is only 25mm long - which means the expansion will occur in the body of the cavity block (which has a wall thickness of about 30mm) rather than in the cavity were you to use a standard rawl bolt. They cost about 20 cent a pop and I was able to buy them individually.

There's a utube video on it I've just noticed so you could check that out. Suffice to say, you want the anchor sitting in the concrete block so you need to drill deep enough to account for any plastering on the surface of the block.

Good luck whatever..

Hollow wall anchors perhaps? One on the left below?

antiskeptic

Fingers McGee wrote: »

Hollow wall anchors perhaps? One on the left below?

The one on the left below looks like a drywall (plasterboard) anchor. The distance between the front flange and the mushroomed back (visualising it fully mushroomed) looks about plasterboard-thickness. Whereas the cavity block I happened across this morn had a wall thickness of about 30-35mm. If you used this item, the section which is supposed to mushroom on tightening couldn't ever deploy, restrained as it would be by being positioned in the block and not free to act in the blocks cavity.

Sheesh, I'm thinking of how my old man used to fix things to the wall. He'd use a special chisel and slowly hammer out a hole, then he'd carve a plug from wood and hammer it home. Aye - but we were 'appier then


-


I could envisage problems with the mushroom fixing principle when applied to cavity blocks. You probably wouldn't get the wall thickness standardisation you have with plasterboard so it's hard to size the fixing correctly. Then there's the problem of the hole being drilled into the blockend or mid-web - you'd need separate fixings for same reasons given above. Then you've a problem when you drill a hole right next to the block end or mid-web > the part of the mushroom right next to the web is restrained from deploying and this could hinder the rest of the mushroom deploying.

kingoffifa

things are getting lively in here!!

i will be heading down to chadwicks on saturday to see these bolts for myself.

again will let ye know how i get on.

LK_Dave

kingoffifa wrote: »

as the title says i am living in a cavity block house.
i wish to fix a pull up/chin up bar to the wall but the screws and plugs that come with it are for a cavity wall. didnt think they were good enough so i went and bought some rawlbolts only to find out that the walls were cavity blocks!

i need this to be fairly secure of course so can someone tell me what type of screw or bolt i should use, and if so where can i get them.

many thanks!!

Did you ever find a solution for this? I'm in the same situation as I want to hang a pull up bar in my garage which has un-plastered (inside wall) cavity blocks.

The cavity block has 40mm thick concrete. I found 30mm wall anchors but the guy in the hardware reckons that they will not hold on the cavity block.

kingoffifa

i found a solution alright.

i put it on a non cavity block wall

cloptrop

get 8 mm rawl plugs dude and some 6 x 50 screws ,,,,, job done

LK_Dave

cloptrop wrote: »

get 8 mm rawl plugs dude and some 6 x 50 screws ,,,,, job done

you are on a hiding to nothing with that solution - the max they hold is about 35kg.

cloptrop

6 spread out holes on it, should be fine , just use 6 x 50 screws not 5 x 50
if it starts wobbling admit defeat and go get something fancy but id say its fine , ive hung very large column radiators on nothing more and they still up

LK_Dave

cloptrop wrote: »

6 spread out holes on it, should be fine , just use 6 x 50 screws not 5 x 50
if it starts wobbling admit defeat and go get something fancy but id say its fine , ive hung very large column radiators on nothing more and they still up

Thanks and I hear what you are saying but nobody is swinging off the column rads!!:rolleyes:

I think I'll mock up a frame using box iron and bolt it to the floor.

EugenesDIYDen

I used six, 10 x 100mm frame fixings for holding up a 40 kilo radiator. Then sat on it, (that's another 70kg!) and it held up with no movement, even though the screws were cantilevered out 62mm because of the wall insulation. This was on a cavity block wall.