Building codes require perimeter drains around the outside of basement footings. They are not difficult to install properly before the foundation has been backfilled, but they are costly and disruptive to put in after the fact.
Sections 404, 405, 406, and 801 of the International Residential Code (IRC) relate to foundations and below-grade habitable space. All code references are to the IRC unless otherwise specified.
Concrete & CMU foundations that contain habitable or usable space need drains [405.1], unless there is good natural drainage [405.1X]. Use filter fabric over drain fields [405.1] and at least 2 inches of stone under pipes [405.1]. If the soil is expansive or collapsible, extend gutter downspouts 5 feet from the building or to an approved drainage system [801.3].
Waterproofing, Damp-proofing, & Backfilling
Below-grade basement walls need damp-proofing [406.1], but if the water table is high, use waterproofing instead [406.2]. Parge CMUs before damp-proofing [406.1], and lap and seal all joints in waterproofing [406.2].
Don’t backfill until foundation walls are anchored to the floor framing [404.1.7] (except walls supporting less than 4 feet of unbalanced backfill [404.1.7X]).
LEED for Homes: ID2 (Durability Management Process) has prerequisites and 3 points for third-party certification of durability processes/practices.
NGBS/ICC 700: Under Ch. 6, Resource Efficiency: 4 points for well-designed foundation perimeter drainage as part of durability measures (602.3).
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