lumpy bubbles

[3nigma]

I've recently had my kitchen extended and noticed slight lumpyness/ bubbles in the finished plaster in places.

At first I thought it may have been attributed to bonding not given enough time to dry. I know it was left for at least 1 day and in places even longer between bonding and multifinish, and from what I've read in posts here that was sufficient.

This seems to occur in patches on both bonding and plasterboard. My plasterer has said I can remove it by lightly sand before painting but I would like to know if it is at all avoidable.

Can anyone PLEASE PLEASE advise how I can avoid this or even reduce as I need to replaster my lounge and want to know if it is bad plastering or somthing else.

 

[stevethespreader]

I've recently had my kitchen extended and noticed slight lumpyness/ bubbles in the finished plaster in places.

At first I thought it may have been attributed to bonding not given enough time to dry. I know it was left for at least 1 day and in places even longer between bonding and multifinish, and from what I've read in posts here that was sufficient.

This seems to occur in patches on both bonding and plasterboard. My plasterer has said I can remove it by lightly sand before painting but I would like to know if it is at all avoidable.

Can anyone PLEASE PLEASE advise how I can avoid this or even reduce as I need to replaster my lounge and want to know if it is bad plastering or somthing else.

these bubbles can appear when troweling up to early bringing the the water to the surface creating the bubbles, or by using to much water if this has happened the plasterer must wait till the finish has gone hard but not set to trowel the bubbles out, if the bubbles are still there its apparent he didn't do this

 

[Richard C]

Steve’s response is on the button; it’s usually down to lack of experience but if your plasterer hasn’t sussed why it’s happening & taken steps to prevent it, maybe time look around for another one.

I would just add that when using a base plaster such as Bonding, you don’t want it to dry out & the finish skim should be applied the same day if possible or at least next day; allowing it to dry out will cause suction problems & it’ll have to be PVA’d before skimming or it’ll go off as you look at it!

 

[mac391]

I'm maticulous about my plastering and been at it 20yrs. Having a few small lumps or bumbs realy isn't too much of a big deal and a light sand will fix it easily. i assume the main job is all to order and you are generally happy with it.

Bubbles like this can appear when a bonding coat is slightly rough and the pva applied before skimming doesn't pentrate small holes in the backing, producing bubbles when skimming. It would only appear on plasterboard though if the board has been damaged. It can happen to the best plasterers but the plasterer should rub it down not the customer. As a simple check, just tap your knuckles on the bubbled plaster on the solid backing to check for a hollow sound.

 

[Richard C]

Having a few small lumps or bumbs realy isn't too much of a big deal and a light sand will fix it easily.

I agree that mistakes happen to everyone once in a while but you can mostly eliminate bubbling when troweling up & you should definitely not have lumps & bumps that need sanding I wouldn’t disagree that sanding the odd blemish or filled trowel mark is fine but sanding new plaster is definitely not a good idea & neither should it be necessary if it’s been properly done. Too much sanding will open up the surface grain making it look like suede brushed the wrong way & will need more paint to hide it.

My point was that if the OP’s spread is making the same mistakes in every room, then he’s not worked out what’s causing it or taking steps to prevent it happening again.

 

[mac391]

If you read the post Richard it's not in "every room" it's just 1, the kitchen. And the problem is described as "slight bubbles" hence my reply.

Having a few small lumps or bumbs realy isn't too much of a big deal and a light sand will fix it easily.

I agree that mistakes happen to everyone once in a while but you can mostly eliminate bubbling when troweling up & you should definitely not have lumps & bumps that need sanding I wouldn’t disagree that sanding the odd blemish or filled trowel mark is fine but sanding new plaster is definitely not a good idea & neither should it be necessary if it’s been properly done. Too much sanding will open up the surface grain making it look like suede brushed the wrong way & will need more paint to hide it.

My point was that if the OP’s spread is making the same mistakes in every room, then he’s not worked out what’s causing it or taking steps to prevent it happening again.

 

[Richard C]

If you read the post Richard it's not in "every room" it's just 1, the kitchen. And the problem is described as "slight bubbles" hence my reply.

Fair comment, my misunderstanding & apologies; welcome to the forum