Frequently Asked Questions (FAQ)
What is Gyvlon® Screed?
Gyvlon® Screed (trademark) is the trade name for the screed range of ANHYDRITEC®. Gyvlon® Screed has been established and recognised in the UK for over 30 years.
What depths of screed are recommended?
Fully Bonded 25mm, mechanical contact with substrate/unbonded 30mm. Over insulation/acoustic matting 35mm domestic and 40mm commercial for our standard Gyvlon screed like ECO & XTR but other variants can go thinner (8mm bonded, 15mm unbonded & 30mm floating) please refer to the product range leaflet
What depth of screed coverage is required over underfloor heating?
Our standard solution, ECO®, requires a minimum of 25mm (by British Standard). BBA Approved Thermio®+ Technology can be installed with just 20mm pipe coverage.
How long before I can walk on the floor?
The screed can be walked on 24 to 48 hours after the installation, dependant on site conditions.
Is it true that I have to sand the screed?
Yes- (ECO, XTR, THERMIO & FINIO) should be sanded after ideally 3 to 10 days post installation (timing dependent on the site conditions) to open up the surface and remove any loose friable material that may have formed to aid the drying process of the screed.
NO- ADVANCED Gyvlon Screeds with E2C they Do NOT require sanding at 3-10 Days post installation because they do not produce loose friable laitance.
But all screeds just before the final floor covering is stuck to the screed should be abraded to remove construction contamination from the surface like plaster, paint, muck, etc by the floor covering layer
Do I have to commission underfloor heating before tiling?
Yes if installing impermeable surface finishes, such as tiles then the UFH must be commission and recorded before the floor covering is laid as per BS1264.
Do I have to prime the screed?
Yes, if any adhesive is used for your chosen flooring, it is recommended to use an epoxy or acrylic primer to stop screed from absorbing the adhesive too rapidly, increasing the amount of adhesive used and limiting the adhesive's open life & performance.
Can I use renewable, solar or low energy sources such as Ground and Air Source Heat pumps with under-floor heating and your screed?
Yes. Thermio®+ is specifically designed to complement these systems by running at lower water temperatures. Saving you money by icreasing the efficinecy of the UFH system used.
Is there help if I have a problem that I cannot find an answer to on the web?
Yes. Please refer to your local Technical Specification Manager (details on our contact us tab) who will assist you.