Page 233 - Construction Waterproofing Handbook

4.8 CHAPTER FOUR
homeowner about avoiding penetration of the waterproofing system by nailing or screw-
ing wall and floor finishes in the basement after occupancy.

Basement waterproofing systems
All the waterproofing systems presented in Chap. 2 for below-grade structures are applic-
able in residential construction as well. However, as mentioned earlier in this chapter, resi-
dential contractors and homebuilders may not have the capability to install the substrate
construction adequately for use of many of the systems presented in Chap. 2. For example,
clay-sheet systems require transition detailing that is beyond the capacity of typical home-
builders. Fluid and sheet systems also have similar transition detailing requirements that
are difficult for typical homebuilders to install adequately.
For the typical residential basement construction, having the contractor install pre-
formed drainage systems both beneath the slab and adjacent to vertical applications, fol-
lowed by installation of a negative waterproofing system with proper cove placement, may
offer the homeowner the best long-term protection against water and mold infiltration in
the basement.
In addition, a number of companies have developed products exclusively for use in res-
idential basements. Often these products are meant for after-construction remedial appli-
cations when the initial systems fail or prove to be installed inadequately. The systems
range from simple water diverters that channel infiltrating water into a sump pump for
removal to the negative waterproofing systems discussed earlier. Some are even marketed
to “do-it-yourselfer” homeowners. All tend to emphasize wall–floor junction repairs, the
most common leakage point in basements.
When selecting any waterproofing system for residential below-grade areas, it is best to
recognize that both workers and supervisors on site generally will be minimally trained,
and therefore, the simpler the system, the better. Any of the prefabricated drainage systems
are excellent choices when used in combination with both positive or negative water-
proofing systems.

ABOVE-GRADE WATERPROOFING

As with below-grade waterproofing, any of the above-grade systems presented in Chap. 3 are
usable in residential construction. However, unlike the difficulty in obtaining expertise to
install below-grade systems, most of the above-grade systems are simple enough for your
average homebuilder to manage properly. However, it is the transitions between envelope
components such as windows and siding joints that again cause 90 percent of water infiltra-
tion. Regardless of how simple the installation of the envelope finish system is, the detail-
ing at terminations and transitions cannot be overlooked.
Average home construction, though, does not usually incorporate any actual above-
grade waterproofing systems, depending instead on the finish materials to act as barriers
themselves, possibly with the simple addition of a paint finish to add water-repellant
capacity. Since residential construction is generally low-rise construction limited to one or
two floors in height, the exposure of the building envelope is minimal, and protecting
against water infiltration is fairly simple.