Question 1

What is a window's U-factor?

Accepted Answer

A window's U-factor measures how much heat passes through it — the lower the number, the better the insulation. It's calculated from the frame's U-factor and the glazing's U-factor, weighted by their share of the window's total area, plus heat loss along the glass edge seal. Frame material matters as much as the glass: wood and wood-aluminum frames consistently post better U-factors than vinyl or bare-aluminum frames, because wood is naturally a poor conductor of heat.

Question 2

What are Low-E windows? What does Low-E glass mean?

Accepted Answer

Low-E (“low-emissivity”) glass has an ultra-thin, invisible metal coating on the pane facing the sealed gap between panes — one coated pane in double glazing, two in triple glazing. That coating reflects heat back toward its source instead of letting it pass through, working alongside the argon gas fill in the sealed cavity to keep heat in during winter and out in summer. It's part of Sorpetaler's standard thermal-insulation glazing.

Question 3

What does "raw density" mean, and why does it matter for a window?

Accepted Answer

Higher density means harder wood — strength, stiffness, and wear resistance all rise with it. Full details, including our standard density requirements, are on our Products FAQ.

Question 4

Does a lower raw density mean lower quality?

Accepted Answer

No — straight-grained conifers like pine and larch can match hardwood strength at a lower density. More on that, and how it applies to each of our wood species, on our Products FAQ.

Question 5

What's the difference between pine, oak, Red Grandis, larch, and meranti?

Accepted Answer

Full materials and construction details are available on our Products FAQ.

Question 6

Why laminated (three-layer glued) profiles instead of solid timber?

Accepted Answer

Three-layer glued scantlings have better static properties and no tendency to warp, which is why Sorpetaler uses them as standard.

Question 7

What are some general home security tips?

Accepted Answer

A few no-cost habits reduce risk more than hardware alone: keep an attentive relationship with neighbors, signal that the home is occupied (timers on lights or a TV), lock all windows and doors every time you leave, add a certified locking cylinder with drill and pull protection, and clear away ladders or bins that make climbing to a window easy. For the technical detail — resistance ratings, mushroom-head locks, front door security features — see the Products page.

Question 8

How do I clean and maintain my windows and doors day-to-day?

Accepted Answer

Wood: mild soap only, no dry rubbing or chemical agents, then a care lotion for weatherproofing. Glass: remove stickers and dirt promptly, plenty of water and mild agents, no blades or scrapers — metal polish removes sealant residue. Aluminum: warm water plus a chlorine-free cleaner suited to an anodized or powder-coated finish, then rinse clear.

Question 9

What should I do to protect my windows and doors during construction?

Accepted Answer

Use a vapour-diffusible cover before plastering. Stick to acrylic-safe masking tape, and remove it within two weeks on wood surfaces. New silicone seals need three to four weeks to cure — clean with water only, no pressure. Keep humidity below 55% during construction; tilt ventilation alone isn't enough. Shield fittings from construction dust, gypsum, and cement, and shade any exposed glazing from heat and direct sun.

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