Bare brick wall - bond coat advice please

[Kevin Price-Ward]

Hi all,

My first post here but just wanted some advice on a project I've started. I'm doing our hall, stairs and landing at the moment (at last after 19 years in the house), taking off the old woodchip has resulted in much of the plaster coming away as well, it was the original crumbly lime plaster! I've basically taken one wall right back to the bare brick (see attached pic and excuse the Villa flag). From what I'm reading I need to apply a couple of coats of PVA then a layer of bond to about 10-15mm thickness - does that sound about right? My main concern is that this wall is very uneven, so how would I go about getting the bond coat flat/level - should I use battens to get it right? If I use battens, when do I take the battens off or do I leave them up. Sorry for such basic questions, complete newbie here!

Many thanks
Kevin

 

[vinn]

Its called dubbing out when you bring an uneven backing wall up to a roughly flat surface. Sand and cement is often used to dub out but you can use whatever you have.
You could use mesh over all exposed wood surfaces, and then two coats of PVA for the whole wall and everything else.
Start plastering as soon as the second coat of PVA goes tacky. Use browning or bonding as a float coat and skim with gypsum finish.
Stairwells can be demanding even dangerous for DIY.

 

[stevethespreader]

Right next to the door frame the previous plasterer has used mesh beads to act as eml so the plaster did not crack if I was doing that job I would float off the door frame if its straight I would use hardwall , if you want you could run a screed up the wall level with the door frame to make it easier for you

 

[Kevin Price-Ward]

When you say 'float off the door frame' do you mean that I'd use the door frame to get it level? What about the other side, would I use a batten there or am I worrying about it being flat and level too much?

 

[stevethespreader]

Yes get your straight edge and rule off door frame other side of what? If walls are uneven use running screed method

 

[Kevin Price-Ward]

I mean the other side of the wall, on the left hand side in the corner or do I just need a flat edge on the one side? Sorry, 'running screed' method - can you explain or point me in the direction of a tutorial?

 

[stevethespreader]

A running screed or dab and screed is where you have an uneven wall you put a dab of render at the top of wall and one at the bottom you then put your level on it once level you infill in between the 2 dots with more render let it firm up a bit and rule off that, you can put as many as you like up you can also rule off both sides of door frame

 

[Kevin Price-Ward]

Ah, OK.... got it. Think I can do that, I guess I'm going to need one of these - http://www.aluminiumwarehouse.co.uk...s_&_Screeding_Levels/c219_335_1295/index.html
Do they make them with levels built in??

 

[stevethespreader]

I've never seen a feather edge with a built in level

 

[Kevin Price-Ward]

OK so I think I know what to do now to get it level but just a couple more questions - sorry! If I'm using sand and cement, is it 6 parts sharp sand, 1 part cement? Anything else that needs to go in the mix? Does it matter at all how long I then leave until I apply the skim coat of plaster? Oh, and what about keying - that seems easy enough but any tips would be fab!

 

[stevethespreader]

If your using s&c you will be better off with plastering sand its going to be easier for you to work with use 4/1 scratch and 5/1 top,use a plasticiser this will make it a lot more workable, after top coat scratch it with figure of 8 patterns for a key (best done with float with nails in the end) then its best to leave it for a couple of days before skim to allow for any shrinking (this is also what the plasticiser is for) it allows you to use less water so not so much shrinkage, just as a note some people skim next day (I've done it myself) but if the times there leave it

 

[Kevin Price-Ward]

I really appreciate you helping me Steve, it's just that the things you say raise more questions in my head! Like I said, I'm a complete beginner - hopefully these are my last questions!!! So, you mention 'scratch' and 'top' - I assume that means 2 layers of render then. So presumably I shouldn't level out the scratch layer, only the top layer? And lastly, just a thought about leveling, if I float off the door frame like you suggested, wouldn't that make the final skim proud of the frame? I thought the idea was to get the final skim level with the door frame to make the architrave fix easily?

 

[stevethespreader]

The skim is tapered into the door frame you can shave a little render off round the frame to accommodate the skim , yes don't bother levelling the scratch coat its only there to provide a key and to dub out just trowel it on and key it up with some wavey lines