Advice On How To Screed A Floor, Floor Screeding
Advice on How To Lay Floor Screeding.
This scenario is a small room with a pier ( boxed pipework ) at one end.
Ensure area to be screeded is free from debris. Also ensure that the sand is stored correctly and free from impurities.
The best mix for floor screed when using a cement mixture is 3 measures of sand to 1 of cement. Soak the floor overnight and brush off the excess prior to commencing work.
As there are 3 types of floor screed, bonded, unbonded and floating, for this scenario, we will be using the bonded method of floor screed. Bonded floor screed is where there is a layer of ‘bond material’ ( called grout ) between the concrete flooring and the screed.
The grout is a ratio of 1:1 mix of sand and cement and should still be wet when applying the screed.the minimum depth for this type of screeding is 25mm and the maximum depth is 40mm.
Brush in the grout onto the wet floor, add PVA to assist with the bonding if required. It is the job of the site foreman to mark datum points for all trades people. If this has not been done, then the datum point around a building is usually the bottom of the door ways or stairs.
Take this point and mark around the wall of the area to be screeded with a marker or other implement such as a chalk line.Starting on the left side of the room, from pier ‘A’ and along wall ‘A’, lay an approximate 30cm wide by 20mm deep Screed up to 1500 mm from wall ‘B’. Pat down this layer of screed until consolidated. Add another layer on top to the required depth which is 40 mm in this case.
The screed should be level with the chalk line on the wall and by using a builders square against the datum point will determine if the depth is correct.Continue this method of screeding around the outside circumference of the area to be screeded.
Once the creed has met the initial screeding against pier ‘A’, place two or three similar screeding lines within the area from wall ‘B’ to the other side of the room.
Each line must be less than 3m apart, as this is the length of the flooring rule being used. Place the rule on top of each line and place a level on top of it to check for levels. Once these screeds are in place, the floor in between must now be filled.
Fill in the spaces between the screeds ensuring that the material is a few millimetres above the already placed screeding.Using the rule, scrape of the excess by drawing the rule towards yourself, ensuring that the wet material is tampered down and any small hollows are filled.
Check all levels at all stages of the procedure and finish in the required method such as float or trowel finish.