Tiling

Extra noggins - is this enough to avoid deflection and cracking of tiles?

Anonymous user 22/10/2025 - 10.03 AM

Hi, I'm renovating my bathroom floor and would like advice on structural support for tiling. I’m planning to use: 15 mm plywood 10 mm insulated cement board (e.g. Marmox) electric underfloor heating mat tile adhesive 60×60 cm porcelain tiles Joists are spaced with a clear 43 cm gap (face to face). I’ll add noggins every 610 mm across, each 100 mm wide, creating a repeated support grid of approx 43×51 cm. Each 2400×1200 mm plywood board will be put across the joints, this means that every board will be supported by 6 joints plus noggins on both long sides (where two boards meet) and in the centre. Is this support layout sufficiently rigid/supportive for large format tiles without flexing over time? Thanks in advance for any advice!

William Cullum

Rating: 5 out of 5

5/54 reviews

Shrewsbury

Not sure how larger your floor is but you only need a single nogin at the halfway point of a 4.5m span so you’ll be fine. 15mm will help remove flex, most people will then use the 6mm cement board mechanically fixed with a bed of adhesive underneath spread with a 6mm trowel. Not sure what you mean by underfloor hearing mat, but I’d look for something like the pro warm carrier mat and a cable over the better versions. It’s also advised to generally use a matting of this type when installing over underfloor heating to help take the movement from the expansion and contractions. Then use a flexible adhesive (most of em these days) and you’ll be good to go

Answered22 October 2025

Like

1

---