Plaster for patching

danrv

Hi
I'm repairing a couple of cracked plaster areas in my hallway. The concrete blocks have separated due to settlement and I've refilled the gaps with mortar.

Ideally the whole wall should be skimmed but I just want to make good as I need to do the floor also.
Would hardwall plaster be ok to use? The depth of the gaps is 15-18mm. I don't really want to have to buy two types.
Any help appreciated.

stuart45

If you've got any sand/cement left over you could use that for the base coats, and get a bag of multi finish for the skim coat. The existing is inferior 2 coats of sand/cement and a siraphite skim.

danrv

stuart45 said:

The existing is inferior 2 coats of sand/cement and a siraphite skim.

The plaster is coming off in large chunks in another area. It appears to be just thick plaster straight onto concrete block.
Seems to be ok for the rest of the hallway.

stuart45

It looks like a sand/cement base cost.

twopenny

When I did this I found a proper base plaster which is quite coarse and a thin skim of finishing plaster gave an really good, unnoticeable result.

After all your hard work and seeing it every time you go out, come in it would be worth making it the best.

Can you not get smallish bags of each? 
It's not as though you can put furniture or a rug over it.

I haven't tried sand and cement mix.

FreeBear

You'd be surprised at just how much bond plaster you'd use to fill out those patches. If you are wanting to keep costs down, I'd suggest heading down to B&Q or Wickes and look for bags of plaster that are split - I've had virtually full bags for £5 each.. Once the holes have been filled with a bonding coat, you'll need very little finishing plaster (probably a quarter bag).

Don't forget to use SBR or PVA on the raw edges.

stuart45

twopenny said:

I haven't tried sand and cement mix.

It used to be the standard method of plastering houses after taking over from lime plaster. 2 coats of sand/cement, and then a plaster skim. In the 70's Carlite plaster started being used, which was Carlite bonding for the base coat and Carlite finish for the skim. It was quicker than the old method, but not really as good. When I built my extension I used sand/cement and then a plaster skim. You don't need angle beads with this method.

danrv

twopenny said:

I haven't tried sand and cement mix.

I'm using that for a base as I have it already.

danrv

FreeBear said:

You'd be surprised at just how much bond plaster you'd use to fill out those patches. If you are wanting to keep costs down, I'd suggest heading down to B&Q or Wickes and look for bags of plaster that are split - I've had virtually full bags for £5 each.. Once the holes have been filled with a bonding coat, you'll need very little finishing plaster (probably a quarter bag).

Don't forget to use SBR or PVA on the raw edges.

I usually pick up a 25kg bag of Multi finish but will look out for split bags.

stuart45

danrv said:

twopenny said:

I haven't tried sand and cement mix.

I'm using that for a base as I have it already.

You need to use 2 coats for that thickness. The first coat needs to be scratched with horizontal stratches. The second coat needs a light scratch with the devil float.

Mr.Generous

I'd be tempted to cut the gap to a square, then stick plasterboard onto the block and skim that. Very easy and cheap way of sorting it.