Flat Roofing Systems

Most low-slope com­mer­cial roof­ing sys­tems have three prin­ci­ple com­po­nents:

Weath­er­proof­ing lay­er or lay­ers — the weath­er­proof­ing com­po­nent is the most impor­tant ele­ment because it keeps water from enter­ing a roof assem­bly.
Rein­force­ment — rein­force­ment adds strength, punc­ture resis­tance and dimen­sion­al sta­bil­i­ty to a mem­brane.
Sur­fac­ing — sur­fac­ing is the com­po­nent that pro­tects the weath­er­proof­ing and rein­force­ment from sun­light and weath­er. Some sur­fac­ings pro­vide oth­er ben­e­fits such as increased fire resis­tance, improved traf­fic and hail resis­tance, and increased solar reflec­tiv­i­ty.

Some com­mer­cial roof­ing sys­tems fea­ture roof mem­branes which may per­form more than one func­tion.

BUR (Built-Up Roof­ing) Sys­tem
A tra­di­tion­al built-up roof­ing (BUR) sys­tem derives its name from the build­ing of a roof on-site using lay­ers of base sheet, inter­ply sheets and cap sheet or oth­er sur­fac­ing such as grav­el or liq­uid coat­ing.

Hot asphalt (bitu­men) is the bond­ing and water­proof­ing agent between lay­ers. BUR is suit­able for most low slope roof­ing appli­ca­tions. The high­er the qual­i­ty of the BUR mate­ri­als and asphalt used and the greater the num­ber of plies (and sep­a­rate asphalt mop­pings), the more supe­ri­or the roof­ing sys­tem.

APP and SBS mod­i­fied bitu­men
In the 1970s, tech­no­log­i­cal advances in asphalt sci­ences led to the devel­op­ment of mod­i­fiers such as APP (atac­tic polypropylene)and SBS (styrene-buta­di­ene-styrene) which, when added to unblown (unox­i­dized) asphalt, impart either plas­tic (APP) or rub­ber (SBS) char­ac­ter­is­tics. These addi­tives pro­vide enhanced per­for­mance char­ac­ter­is­tics to tra­di­tion­al asphalt. When cou­pled with rein­force­ments, such as poly­ester (supe­ri­or elon­ga­tion abil­i­ties) or fiber glass (high ten­sile strength), they cre­ate high-per­for­mance roof mem­branes.

APP mod­i­fied bitu­men mem­branes are self-adher­ing when heat­ed using a roof­ing torch. SBS mod­i­fied bitu­men mem­branes can be for­mu­lat­ed for torch appli­ca­tion, but are more com­mon­ly applied using hot asphalt or cold SBS mod­i­fied bitu­men adhe­sive. The result is a BUR sys­tem with sig­nif­i­cant­ly enhanced per­for­mance capa­bil­i­ties. Con­tin­u­ing improve­ments in tech­nol­o­gy have also result­ed in self-adher­ing SBS roof mem­branes.

When an SBS or APP cap sheet is com­bined with tra­di­tion­al BUR base sheets and inter­ply sheets, the result is a hybrid roof offer­ing the best of both sys­tems – mul­ti­ple plies and supe­ri­or per­for­mance and longevi­ty.

All of these com­mer­cial roof­ing sys­tems are excel­lent choic­es for indus­tri­al, insti­tu­tion­al and res­i­den­tial low slope roof­ing. In choos­ing, fac­tors such as site access, struc­tur­al load, fin­ished appear­ance, desired war­ran­ty and per­for­mance cri­te­ria should all be con­sid­ered. Your Cer­tain­Teed com­mer­cial roof­ing ter­ri­to­ry man­ag­er can help with more infor­ma­tion.

For more infor­ma­tion on Cer­tain­Teed Roofing’s Com­mer­cial Roof­ing Sys­tem­sand prod­ucts vis­it Cer­tain­Teed Roofing’s Low-Slope prod­uct list­ing and Com­mer­cial Roof­ing Sys­tems Tech­ni­cal Infor­ma­tion.

Experts in res­i­den­tial and com­mer­cial roof­ing sys­tems
Cer­tain­Teed is a lead­ing man­u­fac­tur­er of com­mer­cial roof­ing and res­i­den­tial roof­ing prod­ucts and is a divi­sion of Saint-Gob­ain, the world’s largest man­u­fac­tur­er of build­ing mate­ri­als. Saint-Gob­ain ranks among the world’s top 100 indus­tri­al cor­po­ra­tions, oper­at­ing through a glob­al net­work of more than 600 com­pa­nies in more than 50 coun­tries. A qual­i­ty roof depends on two essen­tial ele­ments: excel­lent mate­ri­als and supe­ri­or work­man­ship. Cer­tain­Teed has been one of North America’s lead­ing roof­ing mate­r­i­al man­u­fac­tur­ers for over 100 years.


Mis­sion State­ment: Our objec­tive is to pro­vide our cus­tomers with the high­est qual­i­ty roof­ing, sid­ing, win­dows, gut­ters, and entry door work in the North­ern Vir­ginia & Mary­land areas by offer­ing expe­ri­ence, effi­cien­cy, high qual­i­ty prod­ucts, cus­tomized projects, and the best cus­tomer ser­vice. Our goal is 100% cus­tomer sat­is­fac­tion.

Vision State­ment: Our vision is to be the best roof­ing, sid­ing, win­dows, gut­ters, and entry door replace­ment com­pa­ny in the North­ern Vir­ginia and Mary­land area. Our vision is cen­tered on the cus­tomers’ needs and vision of their home.

Core Val­ues: Our moti­va­tion in each project is direct­ed from our core val­ues. Each core val­ue is cen­tered on the cus­tomer and includes: old time val­ues, con­cern for the cus­tomer, offer­ing the cus­tomer the best prod­ucts, and giv­ing the cus­tomer the best price for the high qual­i­ty prod­ucts.