01Curtain wall
What is the difference between unitized and stick-built curtain wall?
Unitized curtain wall is fabricated and glazed into finished panels in a shop, then hoisted and set as complete units. Stick-built curtain wall is assembled piece by piece at the building — mullions first, then glass — from swing stage or lift. Unitized costs more per square foot but installs faster with less field labor and weather exposure; stick-built is cheaper on smaller, lower, access-friendly elevations.
Read the guide →02Performance
What is a thermal break, and what does energy code require of glazing?
A thermal break is a low-conductivity barrier — usually polyamide strips or poured-and-debridged urethane — separating the exterior and interior aluminum of a frame so heat cannot pass straight through the metal. Energy code regulates the whole assembly U-factor and solar heat gain coefficient, not the glass alone, so frame conductivity, glass makeup and spacer type all count toward compliance.
Read the guide →03Doors & hardware
What do ADA and fire ratings require of commercial entry door hardware?
ADA sets limits on operating force, hardware height, hardware type and closing speed so a door can be used without tight grasping, pinching or twisting. Fire-rated openings require listed assemblies that are self-closing and positive-latching, with no field modifications outside the listing. Where the two conflict — a heavy fire door versus accessible opening force — the resolution is a low-energy power operator, not a weaker closer.
Read the guide →04Weatherproofing
How long does facade sealant last, and when should it be replaced?
Correctly specified and installed silicone facade sealant typically lasts 15 to 20 years; urethane commonly 7 to 12. Service life is shortened by UV exposure, joint geometry that is too shallow or too narrow, missing primer and sealant applied over old sealant. Inspect every two to three years and plan remediation by elevation, since south and west exposures fail years before north.
Read the guide →05System selection
What is the difference between a storefront system and a curtain wall?
Storefront is a non-load-bearing aluminum glazing system installed within a single opening, typically one story and up to roughly 10 feet tall, supported at the head and sill. Curtain wall spans continuously past floor lines and hangs off the building structure at each slab edge. The distinction is structural span and anchoring, not appearance or glass type.
Read the guide →06Procurement
What information does a glazing contractor need to price a commercial scope?
A glazing RFP should state the system type, elevations and opening schedule, required assembly performance (U-factor, SHGC, air and water infiltration, structural design pressure), glass makeup, finish, hardware schedule, access and site constraints, schedule milestones and testing requirements. Missing performance criteria and access constraints are the two omissions that make bids non-comparable.
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