The standard strategy for finishing off masonry walls, as well as a technique still favoured by many plasterers, wet plastering includes applying either a cement-based render or a gypsum backing which can be trowelled right onto the bricks or blocks.For starters, a scratch coat is applied, also referred to as a ‘key’ coat. This forms the base coat that is lightly scratched whilst the plaster remains wet in order to make a great key for that following layer of plaster — the ‘skim’ coat — to bond to.
In addition to cement-based and gypsum plasters, lime and clay plasters are desirable to a great deal of traditionalists and people wanting a wall which can breathe. Lime and clay plasters are higher priced than ‘conventional’ wall finishes plus it may be beneficial to make use of merely a plasterer with expertise in such materials.
A very important factor to look at though: for anyone who is intending on working together with the approach of wet plaster on an external wall, do bear in mind that you won’t be capable of add insulation as you can with plasterboard — except if you are content to utilize external insulation on your own property. So, in case you have got solid brick walls — unlike cavity walls — you should consider the impact which a paucity of insulation might have.
Provides an even, hardwearing finish
Suits traditional properties perfectly
Uncomplicated to apply around difficult areas for instance doors and windows
Offers superb airtightness and soundproofing
Cannot add insulation internally behind this sort of plaster
Takes longer to dry out compared to alternative techniques
Hairline cracking can take place
High skill level is essential — an experienced plaster may be difficult to get and can frequently charge more to do this specific variety of work.
Plasterboard with Skim Coat
There are 2 standard board thicknesses of plasterboard — 9.5mm for 400mm spacings and 12.5mm for 600mm. Additionally, there are various various methods wherein plasterboard may very well be fixed to some wall: ‘dot and dab’ or ‘board on dabs’, and plasterboard that is screwed to timber battens fixed into the wall.
Using dot and dab, sheets of plasterboard are stuck to either brickwork or blockwork walls utilizing dabs of adhesive and allowing simply a modest cavity between plasterboard plus the wall. Along with the batten method — ideal for all wishing to add insulation to a solid wall — timber battens, typically measuring 38mm wide together with a depth to assist the thickness of insulation that you are employing between them, are screwed to the wall.
Rigid board PIR (polyisocyanurate) insulation is going to be inserted between the battens until the plasterboard is defined on the top. A vapour control layer can be necessary with regards to solid walls.
Last but not least, the joints between the boards are covered with scrim tape — usually inside the guise of your self-adhesive tape — just before a skim layer of plaster is trowelled to the plasterboard.
Hairline cracks — which are generally connected with wet plaster — are improbable
Faster drying out time
Possible to undertake using a DIY basis
Insulation could be fitted behind plasterboard
The cavity made could take up room space
Can be challenging to take care of shelving, radiators and pictures
Provides little when it comes to airtightness
Scrim does not always mask the area between your sheets of plasterboard which may be evident through the skim coat.