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Architectural glass,
clearly explained.

Original articles on glass types, fabrication, performance metrics, and US standards, written for all levels, from first-time homeowners to seasoned glaziers.

35+
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150+
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New to architectural glass?

Begin with how glass is made, then learn what makes it safe, what makes it efficient, and how it all comes together in a finished window unit.

1. How glass is made → 2. Safety glass → 3. Energy performance → 4. How IGUs work →

Glass types

What each type of glass is, how it's made, where it's used, and how to specify it correctly.

15 live 15 total
Glass Types · Featured
Insulated glass units (IGU)
How IG units are assembled, primary and secondary seal systems, gas fill options, warm-edge spacers, and what causes seal failure over time. The single most important article for anyone specifying windows.
9 min read · All levels →
Argon fill · Low-E S3
Glass Types
Clear float glass
The foundation of all architectural glass, how it's made, standard thicknesses, ASTM C1036, and when plain clear glass is the right choice.
6 min Beginner →
Glass Types
Low-E glass
What low emissivity means, how coatings block heat transfer, passive vs solar control Low-E, and which surface the coating goes on.
10 min Intermediate →
Glass Types
Tempered glass
How thermal tempering works, why it shatters into small cubes, where it's legally required, and what you cannot do after it leaves the furnace.
7 min All levels →
Glass Types
Heat strengthened glass
Twice as strong as annealed but not a safety glazing material, where heat strengthened fits between annealed and tempered.
5 min Intermediate →
Glass Types
Spandrel glass
Opaci-Coat, ceramic frit, and back-painted options for concealing structure, durability differences, UV resistance, and specification notes.
7 min Intermediate →
Glass Types
Laminated glass
PVB and SentryGlas interlayers, safety ratings, hurricane resistance, acoustic performance, and how laminated glass holds together on failure.
8 min Intermediate →
Glass Types
Acoustic glass
STC ratings, how glass reduces sound transmission, laminated vs monolithic for noise control, and typical performance numbers.
6 min All levels →
Glass Types
Tinted glass
Body-tinted glass, how colorants affect solar performance, matching tints across a facade, and common color designations.
5 minAll levels→
Glass Types
Fire-rated glass
Classes of fire-rated glazing, what each rating means, test standards, and the difference between fire protection and fire resistance.
7 minIntermediate→
Glass Types
Patterned & textured glass
Rolled glass patterns, obscuring levels, light diffusion, privacy applications, and combining texture with safety requirements.
4 minAll levels→
Glass Types
Bird-friendly glass
The ABC 2x4 pattern rule, ceramic frit vs. digital printing vs. UV coatings, which IGU surface to use, and the brands behind it.
9 minIntermediate→
Glass Types
Smart glass (electrochromic)
How electrochromic, PDLC, and SPD films work, current performance limits, and where switchable glass makes sense.
6 minAdvanced→
Glass Types
How mirrors are made
The silvered layer stack, copper-free backing, safety-backed mirrors, and what causes black-edge corrosion.
6 minAll levels→
Glass Types
Low-iron (ultra-clear) glass
Why standard glass looks green, how low-iron removes the tint, the solar-gain trade-off, and where it is worth it.
5 minAll levels→

Fabrication processes

Step-by-step guides to how glass is processed, treated, cut, finished, and assembled at the fabrication plant.

7 live 7 total
Fabrication
Heat soak testing
Why nickel sulfide inclusions cause spontaneous breakage, how heat soak at 290°C reduces that risk, and when HST is required.
7 min Intermediate →
Fabrication
Edge finishing & seaming
Arrised, seamed, flat-ground, polished, and beveled edges, what each finish is, when it's required, and how it affects strength.
5 min All levels →
Fabrication
The tempering process
Step by step through the furnace, heating, quenching, surface compression, and how roller patterns create anisotropy.
7 minIntermediate→
Fabrication
Edge deletion
Why coatings must be removed before sealing, deletion widths for different sealant systems, and what happens when it's skipped.
4 minIntermediate→
Fabrication
IGU assembly process
From raw glass to sealed unit, spacer assembly, gas injection, seal application, quality inspection, and IGMA certification.
6 minIntermediate→
Fabrication
Drilling and notching
Tolerances, hole placement rules, minimum edge distance, and why all holes must be completed before heat treatment.
4 minIntermediate→
Fabrication
Capillary & breather tubes
Why sealed IGUs pillow at altitude, how capillary tubes equalize cavity pressure, and the argon gas-fill trade-off.
6 minIntermediate→

Performance & coatings

U-factor, SHGC, VT, LSG, understanding the numbers that appear on every fenestration product label and energy code document.

4 live 4 total
Performance · Featured
U-factor & SHGC explained
The two numbers on every fenestration label, U-factor measures heat loss, SHGC measures solar gain. Learn how each is calculated, what center-of-glass vs whole-unit means, and how climate zone changes what you should target.
8 min read · All levels →
U 0.10 0.28 0.48 1.0+
Performance
Air side vs tin side
How float glass leaves the tin bath with two distinct surfaces, why it matters for coatings, and how to identify which side is which.
5 minIntermediate→
Performance
Glass coating surfaces 1–4
Surface numbering convention, what coating goes on each surface, and why placement determines performance in hot vs cold climates.
6 minIntermediate→
Performance
Visible light transmittance & LSG
VT, light-to-solar gain ratio, and how spectrally selective coatings admit light while blocking heat, the key to high-performance facades.
5 minIntermediate→

Products & applications

Common finished-glass products and real-world applications: how to specify them correctly and what makes them last.

3 live 3 total
Products & Applications
Shower glass & frameless doors
Why shower glass must be tempered, frameless thicknesses, low-iron clarity, polished edges, and easy-clean coatings.
6 minAll levels→
Products & Applications
Easy-clean & hydrophobic coatings
How water-repellent coatings work, permanent (DFI, EnduroShield) vs. temporary, and how they differ from self-cleaning glass.
6 minIntermediate→
Products & Applications
Glass railings & balustrades
Why glass guards are usually laminated, the mounting systems, interlayers, and the loads and codes they must meet.
7 minIntermediate→

US standards

Plain-English guides to ASTM, NFRC, and IGMA standards that appear on specifications and product data sheets.

6 live 6 total
Standards
ASTM C1036, flat glass
Quality levels, allowable defects, thickness tolerances, and how to read a C1036 specification correctly.
5 minFoundational→
Standards
ASTM C1048, heat treated glass
Heat-strengthened vs fully tempered, surface compression requirements, and fragmentation testing for compliance.
6 minIntermediate→
Standards
ASTM E2190, insulating glass
IGU seal durability testing, fogging resistance, dew point requirements, and what IGMA certification means.
6 minIntermediate→
Standards
NFRC ratings demystified
How the NFRC certifies window and door performance, what the label means, and how to compare products fairly.
5 minFoundational→
Standards
ASTM E1996, hurricane resistance
Missile impact testing, cyclic pressure, and what "impact-rated" actually means for laminated glass assemblies.
6 minIntermediate→
Standards
IECC energy code overview (US & Canada)
Climate zones, prescriptive U-factor and SHGC requirements, compliance paths, and how fenestration fits into the whole-building model. Includes notes on NECB 2020 for Canadian projects.
7 minFoundational→

Glossary of 150+ glass terms

Every technical term used across LiteSpec, emissivity, pyrolytic, MSVD, anisotropy, and 145 more, clearly defined in plain English.

Browse glossary →