I often get asked "just what is screeding?" In a nutshell, screeding (at the very least as practiced in the united kingdom) is really a thin, top layer of material such as for example sand or cement, that is poured along with structural concrete or insulation. This material is then levelled and smoothed so it is the same height because the forms, or guides, that surround it. Imagine an individual measuring a cup of flour, then using a knife to smooth the very best. The flour is compacted and has a smooth top layer. This is screeding in its most basic form.
The most common usage of screeding is in gardening and landscaping. The contractor pours concrete in to the forms or guides and allows it to fill to a particular height. To ensure the concrete will be level when it dries, screeding must be done now. To get this done properly, a tool for instance a long little bit of aluminium or timber, that is bigger than the guides, is slowly moved on the guides. This tool is also moved in a backwards and forwards motion while screeding to level and smooth the concrete, which ensures a perfectly level floor. There are also industrial tools available, which are ideal for use over larger areas.
You can find four main types of floor screeding designs:
Bonded screed
Unbonded screed
Floating screed
Underfloor heating screed
Bonded Screed
This has to be laid on a shot-blasted / scabbled concrete base, and be bonded using an adhesive such as PVA, SBR, epoxy resin or good old-fashioned cement.
Unbonded Screed
These are not bonded directly to the concrete base, but are intentionally debonded with the use of a DPM (damp-proof membrane).
Floating Screed
Floating screed can be used on top of rigid insulation boards. It is strongly recommended that the thickness of a floating screed should be between 65 and 90 mm.
External Rendering Ulverston Heating Screed
A normal sand and cement screed is an ideal choice of screed for underfloor heating. Under floor heating manufacturers and suppliers generally recommend the very least screed depth of 60 mm to utilize with their systems.
The delivery, mixing, and pumping of screed is usually from a single vehicle which pours the screed directly from the mixing pan to the ground at a range of up to 60 metres. For smaller applications, the screed could be hand laid.
Screeding can be left bare to attain a contemporary urban style to the building and it's environment, similar to that in buildings by Japanese architect Tadao Ando, who is renowned for exemplary craftsmanship which evokes a Japanese sense of space. Alternatively other finishing materials could be applied on top.