Slowly permeable layer
A slowly permeable layer is a layer at least 15cm in thickness with the upper boundary within 80cm of the ground surface and with soils that impede the downward movement of excess rainfall.
Ref The HS2 London-West Midlands Environmental Statement, Glossary of terms and list of abbreviations, DETR 2013.
[edit] Related articles on Designing Buildings Wiki
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
CIAT reflects on the party conferences.
CIOB announce the winners of the Art of Building photography competition.
National Scheme of Delegation introduced.
The cost of employing people remains a concern.
Code of Practice for Electrical Energy Storage Systems.
ECA calls on members to comment on draft 4th edition.
Bringing together expertise and creating cultural benefits.
CIOB celebrates positive Ofsted report.
The Building Safety Regulator announces a call for evidence.
Government approach could undermine delivery and regeneration.
World's first mass timber data centre.
The overlooked environmental aspect of data centre development.
Introduction to radon awareness
New technical information sheet published by CIOB.
Updated supplier guide can help electrical contractors engage with NHP.