Replastering a wall-do I need to remove all the old plaster?

[clefty]

Hi All,

We're in the process of renovating our second bedroom. When we bought the place last year, the wall was covered with horrendous cork tiling. It became apparent whilst removing the cork that the plaster underneath was in a very poor state - so we need to replaster the wall.

I've removed the majority of the old plaster pretty easily, however the plaster on the left hand side of the wall is of a much better quality and is proving difficult to shift.

Should I continue to remove it, or is it possible to plaster the rest of the wall and skim over the good stuff?

This is my first attempt at 'proper' plastering - and whilst many of you will probably say 'get a pro in to do it' I would like to learn and attempt it myself before getting someone to do it for me. Especially as we may need to do this in other parts of the house at a later stage.

I've added some pics http://www.diynot.com/network/clefty/albums/ and would appreciate any advice.

Cheers

Claire

 

[stevethespreader]

claire i would take the rest off and then you will be able to put some render beads up, if you get these beads nice and square you will then be able to rule off of them, you will have to get yourself a straight edge to do this its not going to be easy for you, you first have to render ="floatcoat" and then you have to skim it, its no easy task for a beginner the rest off the render should come off in about ten minutes, your not using that crow bar to take it off are you? if you haven't got an sds drill use a hammer and bolster or try the back end of a shovel

 

[clefty]

Hi Steve,

Thanks for the advice, it's confirmed my suspicions.
I did use the crowbar on the majority of the wall as it was literally falling off the walls it took hardly any effort. I've now switched to a hammer/bolster to do the tougher stuff - and the stuff above the windows as I dont want to damage the wood mantle.

I've noticed that the plaster on the left hand side goes much thicker (around 2in) than the rest of the wall - which may make things more interesting.

 

[stevethespreader]

I've noticed that the plaster on the left hand side goes much thicker (around 2in) than the rest of the wall - which may make things more interesting.

you may find that the wall is not straight and thats why its thicker on the lefthand side, it may have needed more render to make the wall straight as it was being floated, also because you are going to use beads your wall will most probably take a new shape, and it wont follow the old lines

 

[peaps]

Hi Steve,

Thanks for the advice, it's confirmed my suspicions.
I did use the crowbar on the majority of the wall as it was literally falling off the walls it took hardly any effort. I've now switched to a hammer/bolster to do the tougher stuff - and the stuff above the windows as I dont want to damage the wood mantle.

I've noticed that the plaster on the left hand side goes much thicker (around 2in) than the rest of the wall - which may make things more interesting.

You will do better if you use a scutch to remove the plaster. I noticed it's lime based render so you will have make sure you have the correct plaster applied. It's also an outside wall so it's even more important to make sure you apply the correct plaster. I would keep to the original lime render.

How old is the house? I would suspect the house has been plastered after it's original build, I wouldn't expect the house to be built with the walls 2" out of plumb so the lime has done it's job by allwing movement over the years. This is another reason for sticking to lime. If you apply the more modern gypsum based backing plasters they are too rigid and will crack with movement. You also have to consider moisture as well, lime render allow the wall to breath, taking in moisture then allowing it to evaporate naturally. If you disrupt this process you can cause problem later on down the line.

You will need to screed the walls to plumb them up, starting at the highest point of the wall. It's a simple process. Any advice needed further just ask.

 

[clefty]

Thanks for the very useful info - I can see I have a lot to learn before I take this on. The house was built in the 30's.

 

[stevethespreader]

I wouldn't expect the house to be built with the walls 2" out of plumb.

You will need to screed the walls to plumb them up, starting at the highest point of the wall. It's a simple process. Any advice needed further just ask.

where did you get the 2in out of plumb from? just because the render on the left hand side is 2 in thick it dosent mean its 2in out of plumb, lets say for instance the other side is an inch thick or an inch and a half thick you have a tolerance of half to one inch, also why would you screed when there are going to be render beads to screed off?

 

[peaps]

I wouldn't expect the house to be built with the walls 2" out of plumb.

You will need to screed the walls to plumb them up, starting at the highest point of the wall. It's a simple process. Any advice needed further just ask.

where did you get the 2in out of plumb from? just because the render on the left hand side is 2 in thick it dosent mean its 2in out of plumb, lets say for instance the other side is an inch thick or an inch and a half thick you have a tolerance of half to one inch, also why would you screed when there are going to be render beads to screed off?

Iwouldn't expect..

Let's just say it quarter of an inch, let's just say is a guess but it out of plumb, until you are at the wall..

Swings and roundabouts.

I think the screeds are all about getting the wall plumb and square. You might allow me to PM you so we can arrage your work visit.....

 

[joe-90]

With energy prices going up and up and up - you've got to think about insulating the walls. Forget about traditional techniques and think about insulated plasterboard. You'll kick yourself in a few years if you don't.

 

[peaps]

With energy prices going up and up and up - you've got to think about insulating the walls. Forget about traditional techniques and think about insulated plasterboard. You'll kick yourself in a few years if you don't.

1930, odds are it's a cavity wall.

 

[clefty]

It's not cavity sadly. I have thought about plasterboard - it might be a better (and easier) option.

 

[joe-90]

Make it the insulated variety.

 

[roy c]

I woulld go with joes sugestion you can over think these situations. If you use 22mm finished insulation board and put a strip of dpc in the corners so the wall doesn't touch the boards and also at the bottom of the boards and cut it off when you put the skirts on that will suffice. If you have damp in the wall then it will only rise to1200mm and it will carry on being in the wall and happily stay there, I have done this in my house and they have 20" thick walls and the rooms are insulated and still dry... I first did this 15 years ago and if you look thru my posts you will find the ones where I described what I have suggested to you...