Building Subfloor Drainage
Building Subfloor Drainage
(OP)
I am designing the subfloor drainage for pier and beam building, with a 6-foot crawlspace. Groundwater is not an issue.
It is a fairly large and geometrically irregular structure, approximately 6.4 acres in area of crawlspace.
The subfloor drainage is only intended to pick up 'emergency' flows, such as a plumbing break in the future. Storm flows are not expected.
Does anyone have an opinion on how I should size these drainage lines? The subfloor drainage will connect to the site storm drain system with gravity flow.
It is a fairly large and geometrically irregular structure, approximately 6.4 acres in area of crawlspace.
The subfloor drainage is only intended to pick up 'emergency' flows, such as a plumbing break in the future. Storm flows are not expected.
Does anyone have an opinion on how I should size these drainage lines? The subfloor drainage will connect to the site storm drain system with gravity flow.





RE: Building Subfloor Drainage
You may get a copy of Architectural Graphic Standards for details. This book shows a detail for non-waterproofed basement walls and floors. The details show 6" perforated drain tile installed at the center line of bottom of footing running under the concrete floor with a min. pitch of 1/8" per foot. Gravel is used to cover the tile.
The drainage opening is a groove in slab or wedge replaced with gravel. The building also has a foundation drain.
You do not mention the shape of your building. The drainage should run across the width of the building to keep the drains at reasonable depth.
RE: Building Subfloor Drainage
RE: Building Subfloor Drainage