C04.03
Keep a wet edge — no lines in our floors
Batches knit together only while both are wet. Lay new material into the previous batch before it starts to set and the floor reads as one piece. Miss it and every tie-in is a permanent line.
- Keep every new batch flowing into the wet edge of the last one
- Hit the tie-in clocks the sheets set — minutes, not vibes
- Plan sections, batch relay, and break points before the first mix
What the sheets actually say
This is not a style preference — it is printed as a requirement. Every MavCrete and MavGrout sheet: 'Lay abutting edges within 10 minutes to ensure a clean edge. A wet-edge installation is imperative during large placements to avoid lines and ridges in the finished floor.' The MavSeal UPA sheet: 'To avoid visible differences in texture or mix-to-mix tie-ins, do not exceed 5–10 minutes from one mix to another.' The broadcast system guides: 'Always leave a wet edge or a thin strip without broadcast to blend in the next mix with the roller.' Three different chemistries, one instruction: the next batch lands in the last batch while the last batch is still wet.
Running a wet edge on a big placement
- 01Plan the sections first
Use control joints and natural breaks as the section lines — the sheets name joints as the legal place for a tie-in. Never plan a stop in the middle of open floor.
- 02Set the batch relay
Mixing never stops while a section is open. One person mixes, the floor crew places. The next batch is ready before the edge of the last one starts to set.
- 03Lay new into old
Empty the fresh batch into the wet edge of the previous one and pull from there — wet into wet, overlapping the previous pass so the two batches become one film.
- 04Back-roll on time, then leave it
Back-roll while it is wet and then stop. Rolling material that has started to tack causes haze, orange peel, and roller lines — the UPA, SLE, HWU, and RCU sheets all carry the same warning. RCU tacks in as little as 5–7 minutes.
- 05Hot or humid? Dip and roll
The UPA and RCU sheets say heat and humidity shorten working time — and that applying by dip-and-roll from a pan in those conditions nearly doubles the usable time. The lead makes that call before mixing, not mid-floor.
- 06Broadcast floors: protect the edge
Leave a thin wet strip without broadcast so the next mix can blend in, and never broadcast into the wet edge until it is settled and back-rolled. Chip or quartz thrown into a working edge is a permanent scar.
- Not this
Finish the pail we have, then mix the next one.
ThisThe next batch is mixing while this one goes down. The edge never waits on the mixer.
- Not this
There's a line — roll it again, it'll blend.
ThisIf it has started to tack, rolling makes haze, not blending. Stop at a joint or call the lead.
Takeaways
- The wet edge is the live boundary of the material you just placed. New material gets laid into it while it is still wet — wet into wet.
- Urethane cements: abutting edges within 10 minutes. Polyaspartics: no more than 5–10 minutes from one mix to the next. Those clocks are printed on the sheets.
- Lines, ridges, and haze at tie-ins are not 'character.' They are a schedule failure the customer walks on for ten years.