We apply and install waterproofing below grade, between slab, on walls, decks, caulk windows and cold joints. We waterproof parking structures, parking and plaza decks, and subterranean garages. The installation of expansion joints of all types falls under our waterproofing division.


Hall of Justice
Scope of Work: PVC Roofing, Waterproofing, Metal Composite, Sheet Metal Flashing & Lourvers

Vertical Walls Coating / Caulking

BEST can Waterproof the exterior walls and if required change the color. Many walls have caulked joints as part of the construction. When these joints deteriorate we are able to clean out the old caulking and install new backer rod and elastomeric caulk.

Spall Repair

Wherever concrete spalls BEST has the skill and experience to conduct repairs. Whether the spall is in the walls of a tunnel or a commercial concrete floor our technicians will conduct repairs and seal against future damage.

Parking Decks / Plaza Decks

Parking decks need to be water resistant, reasonably smooth and typically have anti-skid coatings and resistance to petrochemicals. As with all concrete, cracks lead to water infiltration and eventual spalling with subsequent damage to the tensile load carrying rebar. In addition to other concrete repairs described above BEST can perform necessary repairs to concrete decks, add expansion joints if required and apply traffic surface coatings. These repairs can be applied to exposed (rooftop) or any area where cars are parked including subterranean garages.

The Plaza deck must be coated to be slip resistant and durable to accept foot traffic. This coating must also be waterproof to prevent leaks from rain and the constant watering of decorative plants.

Injection Techniques

BEST uses various injection methods to prevent water ingress under pressure including epoxy and polyurethane systems.

Expansion Joints

Floor expansion joints are usually installed by our Waterproofing Dept. Wall expansion joints are installed by our crews erecting the wall panels.

Concrete Floors

Floor coatings come in many types ranging from the simple epoxy coatings to keep the surface in a condition that permits cleaning to more exotic coatings. These include coatings that resist chemicals including battery acid in an area, for example where fork lifts are recharged; FDA approved coatings including bacteria and fungi resistant and freeze/thaw, thermal shock resistant coatings in areas that are steam cleaned. The floor surface should be free of spalling and damage before being coated.


Los Angeles Police Administration Building
Scope of Work: Waterproofing, Membrane Roofing, Vegetative Roofing

Between Slab Membrane

Originally installed when the building is constructed they can suffer from deterioration. To renew them requires removing the topping slab and the old waterproofing, adding new and replacing the topping slab. These membranes are usually found where there is occupied space below to area where the original membrane is installed, such as roof top parking or on plaza decks over offices or retail space.

Below Grade

Waterproofing below grade carries the highest risk of failure. It therefore requires highly skilled, trained and approved contractors to perform this work. BEST is one such contractor. We apply all types of systems ranging from membrane to liquid applied depending on the specification against foundation walls or lagging systems.