Repointing Blockwork

[bobski1]

Spent the evening removing failing render and screed from an outside wall. It's a party wall where the neighbour has extended but previous owner nor us have. It's been falling apart since we bought the place and now is the time to get it all.

Using the SDS and it's coming off quite easily but some of the pointing is also coming with it so have a few questions on what to do. It's only I'm some areas where it's come away & I'd only repair where needed, not looking to repoint it all unless that's what's needed.

I'm not sure the plan for the wall Mrs B has some ideas but nothing confirmed but for me the main things are to make sure the wall is sound and not to introduce any new issues.

1) is it better to repoint or leave as it is?
2) would you chisel out anymore is it okay to repoint on top of what's there?
3) is a ready-mix okay to use for something like this and any recommendations?

[wolfracesonic]

Is this the outside of an external wall i.e exposed to the weather?

[Lotobear]

The general rule is 2x joint width cut out depth so 20mm if you wnat it to stay put.

..are those aerated blocks?

[bobski1]

wolfracesonic said:

Is this the outside of an external wall i.e exposed to the weather?

Yes, it is external

Lotobear said:

The general rule is 2x joint width cut out depth so 20mm if you wnat it to stay put.

..are those aerated blocks?

It won't be too much effort to get it out especially where it's already popped out or I hit with the SDS. Given it isn't a lot would you use ready-mix?

Doesn't look like it, they look like dense blocks to me. I think I will still need to seal them?

[wolfracesonic]

Looking at how the render has come away cleanly I’d say the blocks are (luckily) 7n concretes, which are reasonably robust as regards frost, unlike breeze blocks. Re pointing make your own mortar, 5 soft building sand to 1 cement. If the wall is in a conspicuous spot, some Sandtex might not go amiss and would help with weatherproofing.

[bobski1]

wolfracesonic said:

Looking at how the render has come away cleanly I’d say the blocks are (luckily) 7n concretes, which are reasonably robust as regards frost, unlike breeze blocks. Re pointing make your own mortar, 5 soft building sand to 1 cement. If the wall is in a conspicuous spot, some Sandtex might not go amiss and would help with weatherproofing.

Yes agree they look like dense blocks to me. I don't have any sand or cement to hand and given it's such a small job I'd rather buy a small tub of ready-mix and apply than have mix and then find somewhere to store half open bags.

[OutInTheShed]

Was the wall ever 'pointed'?
Or was it just laid, then rendered?

If you just point that, I don't think it will be a nice thing to look at.
Also if it's in an exposed place, not ideal for weatherproofness?

If you're going to paint it or coat it, you can probably just do a little 'pointing' with some filler?

Should it really be rendered and painted or some sort of coating?

[Mr Magooagain]

As above,get someone to take a look as it needs preparation and re rendering. Pointing those few joints is a waste of time.

[bobski1]

Not sure if it ever was pointed or just laid and rendered, nobody around to ask.

The plan will be to cover it to make it into a seating area current options are to paint it or to cover with wooden slats whichever way it goes it'll be covered.

I only want to point to avoid any extra ingress then aesthetics second.