Flat Roofing

Many residential and commercial buildings have flat, or low slope, roofs. Most of Philadelphia's row homes have flat roofs and so do many apartment buildings, warehouses, strip malls, skyscrapers, etc. Flat roofs have different requirements than sloped roofs and CD Kaller has solutions for all these types of buildings from small repairs to rebuilds to seal coating.

For homes or buildings where the roof has at least a small slope, Standing Seam Metal Roofing may also be a good option.

Cool Roofs

Some of the types of roofing or sealants described below are available with aluminum or titanium oxide particles, or are naturally white. These type of materials reflect sunlight and can significantly reduce your cooling expense in the summer. Read more about cool roofs.

New/Replacement Roofs

There are 3 main type of flat roofs; Modified Bitumen, TPO and EDPM and each fits different applications. CD Kaller can help you make the best choice.

Modified Bitumen Roofing

Modified Bitumen - also called Torch Down - is a multi-ply roofing system that is often considered the best due to its thickness, durability and flexibility. GAF has several modified bitumen systems available to build your flat roof from the roof decking up. These are multi-ply membranes and can include a layer of insulation. Modified Bitumen systems are ideal for new roofs or complete replacements. The top caps are available in either black or white. White will help reduce cooling costs - see cool roofs above. CD Kaller is a GAF certified Master Elite Contractor.


TPO (Thermoplastic olefin) is another rubber membrane type of roof. TPO sheets are heat-welded together, not glued so they are less prone to separating. This material is white in color which reduces cooling costs. The sun's ultraviolet light, though, can degrade TPO.


EPDM is a synthetic rubber membrane that is attached mechanically to your roof and then the seams are glued together. This type of material is relatively inexpensive, lightweight and easy to install, but has some disadvantages such as shrinkage and damage to the glues, both caused by the ultraviolet rays of the sun. The dark color of the EPDM membrane also absorbs the heat of the sun's rays, adding additional cooling load to your building in the summer.

Seal Coats

Seal Coats are used to seal existing roofs. In some cases - check with us - they can be used to cover over minor damage. Sealcoats are available as asphalt based, silicone or elastomeric acrylics. CD Kaller can help you decide the best choice for your roof.

Silicone Sealers

Silicone sealers can be used to seal existing roofs - especially residential row homes. Sealers such as GACOROOF create a seamless membrane to seal and repair existing roofs and permanently protect against leaks, permanent ponding water and the damaging effects of severe weather. Silicone sealers are excellent for homes, garages and patio covers, sheds and barns.

In addition to sealing your roof, these sealants are also energy efficient, their light color reflects sunlight to save energy.

Roofs treated with GACOROOF can be warrantied up to 50 years depending on the underlying condition of the roof.

Elastomeric Acrylic Sealants

Elastomeric Acrylics are another type of seal coat for existing roofs. These coatings are more for commercial applications and are preferred by many facility managers. These coatings contain various types of acrylic polymer, and are typically formulated to help extend the coating’s life and improve durability. Products that we use like Uniflex from Sherwin Williams are available in a variety of colors including white to reflect sunlight and reduce heat gain in the summer.

Asphalt Based Sealers

Asphalt sealers, sometimes called blackjack or mastic, come in 2 types: water based (low VOC) and solvent based. These are used to seal existing roofs and are available with reflective coatings (silver coat) to reduce heat load due to the sun to save energy. We recommend and use GAF asphalt based products.

Why Choose CD Kaller?