Dot and dab advice

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chief_67

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Hi,

I'm new here and need some advice. I'm near the beginning of renovating my newly purchased 1930's semi detached house. I've taken all the celings down, taken all the old paster off back to the brick work. I've got a DPC guy to install the DPC course in the rooms which had signs of damp done and applied 1m of render from the bottom of the walls that has the DPC course. An old man lived at the house I only used one room in that house and that room had no damp at all. I've now got the dot and dab process started where at the moment the walls are getting plasterboard so no skim yet.

I've been reading up on several forums in regards to damp, cold spots which are pretty frightenming lol so don't know what step to take. The rooms that been dot and dab have no sign of any damp or cold spots or anything to worry about. The house is built of stone from outside and red brick from the inside. I can’t do much about the walls that been dot and dabbed but was thinking the walls that are facing the outside maybe do something with them as maybe they will be the most prone to issues in the future. Was thinking maybe put some damp membrane sheets and then woooden battons and plasterboard onto that and the internal walls can leave them as dot and dabbed. Or do you think I’m just stressing out for no reason. Really need some help as I don’t know what step to take.

Thanks in advance
 
Welcome

If you have damp there’s a reason behind it so you’re better off finding the issue; blown bricks, damaged render, mortar, bad seals, vegetation near walls of house etc etc. Find it and solve it.

Sounds like the house probably had damp because the old fella used one room and likely only heated that one room. Houses need warmth and ventilation.

You’re probably be fine dabbing but alternatives are floating s/c or you could even dab thermal board onto exterior walls to keep them toasty.

Get a few spreads round to take a look and advise you.

All the best
 
Hi,

The DPC guy mentioned it could be that the old fella only used one room and that room happen to have no damp at all and the other rooms were never used which they weren't going by what the neighbours told me. He also checked the walls for me and said they seem pretty solid. The mortar in between the bricks look good etc. Was planning to do the pointing/rendering from the outside closer to spring when the weather gets warmer.

Fingers crossed I won't have any major damp issues in the future but my main concern is the cold spots problem that people tend to have when dot and dabbing where the adhesives point are coming through the plasterboard, that's my main concern.

Was also thinking sand+cement wet plaster the exterior walls. But there some people that advise that the walls do need to breath so you don't want to cut the insulation out completely especially on old houses as you will have problems later.

Just to add the walls that have been dot and dabbed at the moment have been like that for about a month, they are not skimmed yet, and there no known issues of cold spots damp etc and its been like -1 degrees to 2 degrees celsius past couple of weeks but its been cold in the house aswell as outside. Also want to say that the exterior walls are stone from the outside then a gap which is more or less full of rubble which had happen over the years, then the inside is a brick wall do you think the gap of rubble in between the be used as a insulation, I don't want to insulate the inside walls further and restrict insulation and have further problems.

Thanks in advance
 
Can I dot and dab thermal boards like normal plaster board with drywall adhesive, or is there another way to do this.
 
What do you think guys is dot and dab the external walls using thermal boards the best thing to do. To avoid any damp issues or cold spots in the future etc. The house is all back to brickwork, luckily only 1 external wall has been plasterboarded so will get that ripped off and put thermal boards on. What you think guys, been stressing out about this lol.
 
What about using foam plaster board adhesive? I've never tried it but I assume it will prevent moisture being drawn through to board? Maybe someone else on here has used it and can say if any good.
 
I would find out why it was damp before I spent money or did anything else.

Not heating a room will not make it go damp. It will go damp because there is an issue with either water penetration or condensation. Even if you had heating in that room with water penetration you would still have damp. The only problem heating would solve would be condensation which would then reapear when the room is cold again.

Condensation would be caused by a cold wall...........warm air from other rooms cooling on your cold wall or spot and turning to water. This is usually towards the top of the wall or around windows etc. Rising damp is always at bottom to about 1 meter up.
 
Feck this said:
What about using foam plaster board adhesive? I've never tried it but I assume it will prevent moisture being drawn through to board? Maybe someone else on here has used it and can say if any good.
Click to expand...
Obviously any penetrating damp needs addressing to cure problem. But if cavity is being bridged by rubble, I think it won't take much for problems to keep arising. So like others have said insulated board is probably best. But I'd be worried about cement based board adhesive bridging damp onto board.
 
Also if wall is damp and cant be cured because of rubble as Feck this points out. Then any adhesive is going to struggle to be effective isnt it?
 
satan said:
I would find out why it was damp before I spent money or did anything else.

Not heating a room will not make it go damp. It will go damp because there is an issue with either water penetration or condensation. Even if you had heating in that room with water penetration you would still have damp. The only problem heating would solve would be condensation which would then reapear when the room is cold again.

Condensation would be caused by a cold wall...........warm air from other rooms cooling on your cold wall or spot and turning to water. This is usually towards the top of the wall or around windows etc. Rising damp is always at bottom to about 1 meter up.
Click to expand...

The previous owner was an old fella and only used one room and that room happen to have no damp at all and the other rooms had damp on the lower part of the wall going by the damp reading the rest of the wall was fine, that was the situtaion for 10 years going by what the neighbours tell me there was no heating in that house aswell apart from the room he used. DPC guy also checked the walls for me and said they seem pretty solid. The mortar in between the bricks look good etc. Was planning to do the pointing/rendering from the outside closer to spring when the weather gets warmer. DPC guy boiled it down to the room not having the ventilation, heat etc needed for such a long time resulting in the damp towards the bottom
 
Feck this said:
Obviously any penetrating damp needs addressing to cure problem. But if cavity is being bridged by rubble, I think it won't take much for problems to keep arising. So like others have said insulated board is probably best. But I'd be worried about cement based board adhesive bridging damp onto board.
Click to expand...

I'm leaning towards insulated boards aswell.

When you say cement based board adhesive you mean the driwall adhesive used to dot and dab normal plasterboard.
 
chief_67 said:
I'm leaning towards insulated boards aswell.

When you say cement based board adhesive you mean the driwall adhesive used to dot and dab normal plasterboard.
Click to expand...
Why don’t render in sand and lime let the property breathe.
 
satan said:
Also if wall is damp and cant be cured because of rubble as Feck this points out. Then any adhesive is going to struggle to be effective isnt it?
Click to expand...

I don't have any damp issues or any issues at the moment, the damp I had at the bottom of the wall has been addressed. The walls have been taken back to brickwork and ready to be dot and dabbed the concern I have is i want to take precautions in avoiding damp or cold spot issues. And I think to avoid this I will be using thermal insulation boards on all the external walls using the dot and dab way and dot and dab the internal walls using normal plaster board. I think that will be the best way forward to avoid issues in the future.
 
chief_67 said:
The previous owner was an old fella and only used one room and that room happen to have no damp at all and the other rooms had damp on the lower part of the wall going by the damp reading the rest of the wall was fine, that was the situtaion for 10 years going by what the neighbours tell me there was no heating in that house aswell apart from the room he used. DPC guy also checked the walls for me and said they seem pretty solid. The mortar in between the bricks look good etc. Was planning to do the pointing/rendering from the outside closer to spring when the weather gets warmer. DPC guy boiled it down to the room not having the ventilation, heat etc needed for such a long time resulting in the damp towards the bottom
Click to expand...
Well a half decent damp meter costs but a few quid and you can spend many hours driving yourself nuts playing with it around your house.

Where the old guy lived is not really relent now as you have to find out where the damp is coming from.

Buy a good dehumidifier and stick it in the room which is damp and see what happens with your damp meter before and after. If its just condensation it will soon dry. Then that meter and dehumidifier has saved you a lot of money and heartache. If the damp returns then at least you know you have a problem. Until you dry it out you will never know.

Pointing brickwork only replaces the mortar to stop rain penetrating. It does not stick the bricks together. That is done by weight when laid.

If a cavity wall then pointing is not really your damp problem. That can only happen if the damper exterior wall can transfer damp to the inner wall. This means something is bridging the cavity. Could be rubble, dirty brick tie, birds nest, insulation anything.

Dehumidifier for job.............call 01423 341 940 and ask for Simon...........sound fella........he will sort you out.
 
chief_67 said:
I don't have any damp issues or any issues at the moment, the damp I had at the bottom of the wall has been addressed. The walls have been taken back to brickwork and ready to be dot and dabbed the concern I have is i want to take precautions in avoiding damp or cold spot issues. And I think to avoid this I will be using thermal insulation boards on all the external walls using the dot and dab way and dot and dab the internal walls using normal plaster board. I think that will be the best way forward to avoid issues in the future.
Click to expand...
I wrote war and peace before I saw above post.

How did you 'address' damp issue?
 
Bagrat said:
Why don’t render in sand and lime let the property breathe.
Click to expand...
That was one option I read about, I think this will not be do-able as not a lot people do that in west yorkshire due to dot and dab being introduced. I think thermal insulation plaster board will be my best option, same procedure as dot and dab and also address the issue of not having any future cold spot or damp issues. If I render in sand and lime isn't there a risk of damp still returning in the future.
 
chief_67 said:
That was one option I read about, I think this will not be do-able as not a lot people do that in west yorkshire due to dot and dab being introduced. I think thermal insulation plaster board will be my best option, same procedure as dot and dab and also address the issue of not having any future cold spot or damp issues. If I render in sand and lime isn't there a risk of damp still returning in the future.
Click to expand...
Dunno unless you say how you addressed damp problem.............conflicting info here??????
 
chief_67 said:
By injecting damp proof course on the infected walls and then applying 1 meter of sovereign render lite plaster starting from the bottom.
Click to expand...
OK understand now. Have you tested walls for damp since? If damp where located? No damp why are you asking about cold spots?
 
chief_67 said:
Hi,

I'm new here and need some advice. I'm near the beginning of renovating my newly purchased 1930's semi detached house. I've taken all the celings down, taken all the old paster off back to the brick work. I've got a DPC guy to install the DPC course in the rooms which had signs of damp done and applied 1m of render from the bottom of the walls that has the DPC course. An old man lived at the house I only used one room in that house and that room had no damp at all. I've now got the dot and dab process started where at the moment the walls are getting plasterboard so no skim yet.

I've been reading up on several forums in regards to damp, cold spots which are pretty frightenming lol so don't know what step to take. The rooms that been dot and dab have no sign of any damp or cold spots or anything to worry about. The house is built of stone from outside and red brick from the inside. I can’t do much about the walls that been dot and dabbed but was thinking the walls that are facing the outside maybe do something with them as maybe they will be the most prone to issues in the future. Was thinking maybe put some damp membrane sheets and then woooden battons and plasterboard onto that and the internal walls can leave them as dot and dabbed. Or do you think I’m just stressing out for no reason. Really need some help as I don’t know what step to take.

Thanks in advance
Click to expand...
if u have the room frame it all out /no matter what don't put sand and cement in there
 
satan said:
Well a half decent damp meter costs but a few quid and you can spend many hours driving yourself nuts playing with it around your house.

Where the old guy lived is not really relent now as you have to find out where the damp is coming from.

Buy a good dehumidifier and stick it in the room which is damp and see what happens with your damp meter before and after. If its just condensation it will soon dry. Then that meter and dehumidifier has saved you a lot of money and heartache. If the damp returns then at least you know you have a problem. Until you dry it out you will never know.

Pointing brickwork only replaces the mortar to stop rain penetrating. It does not stick the bricks together. That is done by weight when laid.

If a cavity wall then pointing is not really your damp problem. That can only happen if the damper exterior wall can transfer damp to the inner wall. This means something is bridging the cavity. Could be rubble, dirty brick tie, birds nest, insulation anything.

Dehumidifier for job.............call 01423 341 940 and ask for Simon...........sound fella........he will sort you out.
Click to expand...

Can a damp reader still give reading on a wall that's gone back to brick work.

I thought i can only use the dehumidifier once the walls been plastered whichever metod i use in the house either dot and dab or sand cement etc. I don't see the point of putting a dehumidifier in when it just bare brick, isn't it best plastering the walls then get it in.
 
The Hobo said:
if u have the room frame it all out /no matter what don't put sand and cement in there
Click to expand...
Newbie answer but I take you mean the batton method, so damp membrane wooden battons screwed into the brick then plaster board onto the battons. You don't recommend sand and cement the walls.

How about thermal insulation plaster board what's your thought on them using them on just the external walls.
 
chief_67 said:
Can a damp reader still give reading on a wall that's gone back to brick work.

I thought i can only use the dehumidifier once the walls been plastered whichever metod i use in the house either dot and dab or sand cement etc. I don't see the point of putting a dehumidifier in when it just bare brick, isn't it best plastering the walls then get it in.
Click to expand...
keep off the solid walls defo don't dot and dab see your damp meter put it in dustbin they don't work just make survayers look smart
 
chief_67 said:
Can a damp reader still give reading on a wall that's gone back to brick work.

I thought i can only use the dehumidifier once the walls been plastered whichever metod i use in the house either dot and dab or sand cement etc. I don't see the point of putting a dehumidifier in when it just bare brick, isn't it best plastering the walls then get it in.
Click to expand...
You can use a damp meter where ever you like.............well almost as you may get a slap and arrested. :p

If the damp man has cured your problem then what you are really asking is how to insulate a wall with no insulation.

If it were me and my house.............I would line the wall with a membrane (plastic). I would then put 50mm kingspan on or up against wall. I would make a new studded wall out of 2"x2" and fill inbetween studding with more kingspan so that you have almost 4"/100mm insulation. Then sheet it out with 18mm osb board and cover with a membrane (plastic). Then board out and possibly skim.

Result over the top but by just a few quid £100.......extremely well insulated wall that is super strong to fix things to without fear of penetrating membrane on old wall and no damp return......and a very warm room.
 
Last edited:
satan said:
OK understand now. Have you tested walls for damp since? If damp where located? No damp why are you asking about cold spots?
Click to expand...
I dont have any issues with cold spots it just that I'm a stress freak and I read that people who dot and dab have had cold spot issues circles around the adhesive spots. And coz I'm dot and dabbing I think it might happen to me so want to take precautions. I know what you thinking I'm going OTT lol.
 
chief_67 said:
Newbie answer but I take you mean the batton method, so damp membrane wooden battons screwed into the brick then plaster board onto the battons. You don't recommend sand and cement the walls.

How about thermal insulation plaster board what's your thought on them using them on just the external walls.
Click to expand...
thinking more of stud work dpc below insulate etc
 
satan said:
You can use a damp meter where ever you like.............well almost as you may get a slap and arrested.

If the damp man has cured your problem then what you are really asking is how to insulate a wall with no insulation.

If it were me and my house.............I would line the wall with a membrane (plastic). I would then put 50mm kingspan on or up against wall. I would make a new studded wall out of 2"x2" and fill inbetween studding with more kingspan so that you have almost 4"/100mm insulation. Then sheet it out with 18mm osb board and cover with a membrane (plastic). Then board out and possibly skim.

Result over the top but by just a few quid £100.......extremely well insulated wall that is super strong to fix things to without fear of penetrating membrane on old wall and no damp return......and a very warm room.
Click to expand...
If i did go down this route should I just do this on external walls (walls that are facing outside)
 
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