Which wall anchors? (Rawlplugs not working)

[zcacogp]

Chaps,

I'm making some built-in wardrobes for zcacogp towers. Going in the master bedroom, and comprising a frame which the doors hang on, which is screwed to the walls.

The house is a Georgian terrace, and one of the walls that the frame screws onto is proving difficult. It is an original wall (dating back to the time the house was built, so 1890's), and I think it has the original plaster on it. Drilling into it has shown that it is not consistent in construction; it is very crumbly and produces large amounts of gritty grey dust when drilled, and it seems to have pockets in it, some of them quite large. While I am sure it is structurally sound it is very crumbly indeed. (An SDS drill on hammer setting makes holes far bigger than the drill bit; on non-hammer it fares a little better.)

The wall is also not straight, and screwing the wardrobe frame onto it requires the frame to bend to follow the curve of the wall. Therefore there is a significant amount of force exerted on whatever wall anchors are used.

And therein lies the problem. I am using rawlplugs (large brown ones), but they aren't working. They spin in the holes, and if they do grip enough to get the screw in, they pull out very readily. I currently have them at (approx) 60cm intervals, and they simply aren't holding.

What other options are there? Butterfly spring-open clips aren't an option as there is no cavity in which to spring them. Deeper frame-mount things could be an option, but I am not sure whether they would be radically much more successful than rawlplugs - although I am willing to have a go (I guess the question is whether, if I put deeper fittings in, they would get to a brick core to the wall which would be stronger.) I have no expereince of the resin-filling anchor systems, or anything else, but am willing to learn.

Any suggestions? All welcomed ...

Thanks.


Oli.

[530dTPhil]

We have used studs/bolt fixings set in resin with complete success when trying to fix steel racking to all sorts of bricks and blocks, including thermalite. Quite readily available and easy to use; sounds like what you need.

[zcacogp]

Phil,

Thanks. Does that include crumbly walls that turn to grit at the touch of a drill bit?

Do you have a link to the sort of thing you are talking about? Is it something like this:

http://www.screwfix.com/prods/33554/Fixings/Inject...


Oli.

[hman]

sounds like a job for resins, or those metal heavy duty anchor point thingys, but they are huge.

[mgtony]

To start with, it would help if you didn't have the spring in the frame. Is there enough timber on the frame to scribe it to the shape of the wall or put in a filler piece?
You could try filling the holes with Gripfill then putting the plug in and letting it to set before screwing into.
There are a couple of fillers out there that claim you can screw straight into or put a plug into.
Hope this helps.

[StoatInACoat]

My house is the same. I found using smaller plugs (red ones) was the answer because then I could run a much smaller drill bit on a lower speed without the need to resort to seemilngly hours on hammer trying to drill the brick underneath. With the 9mm bit I was pulling big sections of plaster off the wall and doing a lot of damage.

Used fibre plugs in the kitchen to hold the units up although I'm not sure you can buy them anymore...

Edited by StoatInACoat on Monday 31st January 10:07

[cjs]

Try drilling a test hole to see if you hit brick, then get longer screws. Or as above, get some gripfill in with the brown plugs, let it set for a hour or so, done this many times with good success.

[Simpo Two]

zcacogp said:

The house is a Georgian terrace... dating back to the time the house was built, so 1890's

They don't teach history any more do they

zcacogp said:

it is very crumbly and produces large amounts of gritty grey dust when drilled, and it seems to have pockets in it, some of them quite large. While I am sure it is structurally sound it is very crumbly indeed. (An SDS drill on hammer setting makes holes far bigger than the drill bit; on non-hammer it fares a little better.)

The wall is also not straight, and screwing the wardrobe frame onto it requires the frame to bend to follow the curve of the wall. Therefore there is a significant amount of force exerted on whatever wall anchors are used.

Deeper frame-mount things could be an option, but I am not sure whether they would be radically much more successful than rawlplugs - although I am willing to have a go (I guess the question is whether, if I put deeper fittings in, they would get to a brick core to the wall which would be stronger.) I have no expereince of the resin-filling anchor systems, or anything else, but am willing to learn.

I think a SDS hammer drill is far too violent for a delicate wall. I'd use an ordinary drill and use 4" window frame fixings. Don't try to bend the frame to fit the wall; use spacers so the frame is straight. This will mean the structure isn't needlessly stressed.

[mhill]

Had a similar problem and couldn't find anything to work, it was suggested i drilled the hole place the largest plug in the hole and fill with a ultra strong resin based adhesive to fill. Wait for it go semi hard then screw into into it. The trick id finding the correct adeshive though......

[Laurel Green]

Plaster alone will not hold the fixing; best to drill through the plaster and into the brickwork. As already said, either plane the wood to fit the curve in the wall or, cut wedges of wood to, er, wedge where not fitting to wall.

[thinfourth2]

Doesn't sound like lath and plaster which would tie into that age so it must be plaster directly onto the brickwork.

Go old school. Drill a large hole 12mmish. Then whittle a wooden plug and batter it into the hole. Cut it off flush with the wall. Then screw into it.

[Deva Link]

Our internal walls are crumbly cinder block and I found some "squashy" wall plugs worked well - bit like this kind of thing:



There doesn't have to be a void - they expand and fill the hole anyway.

[Dogwatch]

As others have commented, curving the batten to the wall doesn't sound like good practice whatever the state of the wall.

Regarding the oversize fixing holes Wickes sell a pack called Wet N Fix. Basically small patches of bandage type material impregnated with plaster of Paris, just like the stuff they use for broken limbs in A&E. Wet the patch, wrap it (or two) round the Rawlplug and stuff it in the hole. PofP dries out in 3 minutes and fixing is steady as a rock. Has saved my bacon once or twice! :shame:
I would expect other DIY sheds sell something similar.

[TooLateForAName]

I've used hammerfixings as the only reliable way of getting anything to stay fastened to the wall. But as others have said, use spacers or fillets between the frame and the wall.

[jas xjr]

i saw some screws a window installer was using. it is just a screw and is simply screwed into the wall. no plug required . might not be 100% what you are looking for but they were very impressive. straight into the brick.

anybody know what they are called?

[Ricky_M]

Have you tried drilling a smaller hole? Try using a 5.5 or 6mm bit for a brown plug. Also get some longer screws and drill a lot deeper.

I find this a lot on old town houses, quite a large layer of decaying plaster and render on top of solid stone. You need to drill quite deep to hit the stone.

[Deva Link]

jas xjr said:

i saw some screws a window installer was using. it is just a screw and is simply screwed into the wall. no plug required . might not be 100% what you are looking for but they were very impressive. straight into the brick.

anybody know what they are called?

Masonry screws. They work well in brick and other non-crumbly stuff, but you defintiely don't want the hole to be oversized or there's nothing for the threads to bite in to.

[dave_s13]

Ricky_M said:

Have you tried drilling a smaller hole? Try using a 5.5 or 6mm bit for a brown plug. Also get some longer screws and drill a lot deeper.

I find this a lot on old town houses, quite a large layer of decaying plaster and render on top of solid stone. You need to drill quite deep to hit the stone.

Worth a try.

You need to knock the rawl plug as far into the hole as you can before screwing into it though.

[dave0010]

jas xjr said:

i saw some screws a window installer was using. it is just a screw and is simply screwed into the wall. no plug required . might not be 100% what you are looking for but they were very impressive. straight into the brick.

anybody know what they are called?

I thought they had a stupid name like thunder bolts? normally drill a 8mm hole first and then bang them in with a socket on the end of a drill.

[Deva Link]

dave0010 said:

I thought they had a stupid name like thunder bolts? normally drill a 8mm hole first and then bang them in with a socket on the end of a drill.

Thunderbolts are big masonry screws. They come in a range of sizes.