Heyen UK damp-proofing News
Basement Performance Levels - What is dry?
| GRADE OF BASEMENT | RELATIVE HUMIDITY | TEMPERATURE | PERFORMANCE DAMPNESS | LEVEL OF WETNESS |
| Grade 1Basic Utility | >65% Normal UK External Range. | Car Parks: Atmospheric, Workshops: 15-29 degrees C. Mechanical Plantrooms 32 degrees C Maximum at ceiling level. | Visible damp patches may be acceptable. | Minor seepage may be acceptable. |
| Grade 2 Better Utility | 35-50% |
Retail Storage: 15 degrees C Maximum. Electrical Plantrooms 42 degrees C Maximum. |
No visible damp patches, construction materials to contain less than the air dry moisture content. | None Acceptable. |
| Grade 3 Habitable |
40-60% 55-60% for a restaurant in Summer |
Offices: 21-25 degrees C. Residential 18-22 degrees C. Leisure Centres: 18 degrees C Spectators. 10 degrees C Squash Courts. 22 degrees C for changing rooms. 24-29 degrees C Swimming Pools. 18-25 degrees C Restaurants.
|
None Acceptable: Active Measures to Control internal humidity may be necessary. | None Acceptable. |
| Grade 4 Special |
50% for art Storage. >40% for Microfilms & Tapes |
Art Storage 18-22 degrees C. Book Archives 13-18 degrees C. |
Active Measures to control internal humidity probably essential. | None Acceptable |
Grade 1 - Some water leaks may be permissible. No requirement for relative humidity control.
Grade 2 - No leaks Permissible. There will seldom be a need for relative humidity control.
Grades 3 & 4 - No leaks permissible. Relative humidity to be kept to a level appropriate for the usage of the basement.