About
Why these notes exist
A site supervisor writes these pages between inspections. Each page collects the measuring method, the reference length and the acceptance figure used on renovation and fit out jobs, set out in the order the checks happen on site.
01.Why do renovation disputes need measured figures?
Renovation disputes run on adjectives until somebody produces an instrument. A client calls a wall wavy, a plasterer calls the same wall fine, and the argument lasts three weeks. A measured gap of 7 mm under a 2 m straight edge against an agreed limit of 3 mm ends the same argument in four minutes.
Every page here therefore pairs a number with a method. A gap of 4 mm carries no meaning until the length of the straight edge appears next to the gap. A screed reading of 78 percent carries no meaning until the hygrometer sealing time, the box position and the room temperature appear beside the reading. The table below lists the instruments that produce the figures, and the resolution each instrument reads to.
Table 1. Instruments used across the four procedures
| Instrument | What the instrument measures | Reading resolution (mm, percent or degrees) | Check or calibration interval (months) | Procedure page |
|---|---|---|---|---|
| 2 m aluminium straight edge | Surface deviation over a 2000 mm reference length | 0.05 mm, read with feeler gauges | 1 | Plaster, screed, tiling |
| 300 mm straight edge | Local step at beads, reveals and tile joints | 0.05 mm, read with feeler gauges | 1 | Plaster, tiling |
| Feeler gauge set | Gap width between an edge and a surface | 0.05 mm per blade, 0.05 mm to 5 mm | 6 | All four procedures |
| Dial gauge | Tile lippage where a dispute is likely | 0.01 mm | 12 | Tiling |
| Joint gauge | Grout joint width and door leaf gaps | 0.5 mm | 12 | Tiling, punch list |
| Surface hygrometer box | Relative humidity of a screed after 72 hours sealed | 1 percent RH | 12 | Screed |
| Carbide bomb kit | Screed moisture by weight from a drilled sample | 0.1 percent by weight | 12 | Screed |
| Pin type moisture meter | Plaster surface moisture before decoration | 1 percent WME | 12 | Plaster |
| Digital thermohygrometer | Room temperature and relative humidity during drying | 0.1 degrees Celsius and 1 percent RH | 12 | Screed, plaster |
| Nylon tipped tapping rod | Loss of contact between a bed and a tile or render | Pass or fail, no numeric reading | No calibration | Tiling, plaster |
| Crack width gauge card | Width of a shrinkage crack in plaster or screed | 0.1 mm | No calibration | Plaster, screed |
| Depth probe | Screed thickness during the pour, on a 3 m grid | 1 mm | 12 | Screed |
Check intervals are working habits rather than a manufacturer requirement. A straight edge that has been dropped gets checked the same day, whatever the interval column says.
02.Where do the tolerances on this site come from?
Three sources feed the tables on Xay Dung Viet Phu: project specifications, which name the acceptance limit for one job; product data sheets from adhesive, screed and plaster manufacturers, which carry the limits a warranty depends on; and site experience, usually in the form of the tighter figure that avoids a second visit.
Published standards sit behind many of the values, and grade names such as SR1, SR2 and SR3 follow the wording that appears in most floor specifications. No page on Xay Dung Viet Phu quotes a standard clause number, because a clause number copied without the standard in hand is worth less than no reference at all. Read the clause that applies to your own contract before quoting any figure from these pages in a rejection notice. Where a project specification and a table here disagree, the specification wins.
How to use the pages during a handover
- Read the relevant procedure page the evening before the inspection, not during the walk
- Copy the acceptance row that applies into the room data sheet before the trade starts
- Carry the instruments listed in the facts block at the top of each procedure page
- Write the instrument and the reference length next to every measurement in the register
- Photograph each defect with the gauge still in place and a numbered marker card in frame
- Give the trade the measured value, the agreed limit and the location in one sentence
- Re inspect within 48 hours of a trade reporting the repair complete
03.What does this site not cover?
Xay Dung Viet Phu covers finishes and workmanship only. Structural design, fire compartmentation, electrical certification and gas work belong to specialists holding their own qualifications and issuing their own certificates. A supervisor measuring plaster with a 2 m straight edge does not sign off a consumer unit or a flue test.
Where a check on one of these pages touches a regulated trade, the page names the certificate to collect rather than a test to run. The underfloor heating commissioning record on the screed page is one example: the supervisor collects the dated record of flow temperatures, and the heating engineer signs the commissioning itself.
04.How often do the figures on this site get corrected?
Tolerances change as products change, and a figure that suited a 300 mm pressed ceramic tile in 2012 does not suit a 1200 mm porcelain slab in 2026. Pages on Xay Dung Viet Phu get updated when a project specification, a product data sheet or a recorded site failure produces a better figure than the one already published.
Any reader holding a specification clause that contradicts a table here is probably right for that job. A contract clause governs the work on the job it was written for, and a working figure on a public page never does.