How to choose window film: daylight, heat and glazing
What to compare before tinting: visible light, solar energy, reflection and compatibility with your glass.
Start with the problem
Write down the issue: afternoon heat, glare at a workstation or views from the street. These require different decisions. Add window orientation and when the problem is most noticeable. This is more useful than asking for the darkest film.
Compare matching measures
VLT describes visible light transmission. TSER is the proportion of total solar energy rejected by the glass-and-film system. IR concerns the infrared range; a high IR figure does not mean the same reduction in total solar energy. Ask for a specification that identifies the glass used for the figures.
Check the sample and glazing
Assess a sample at your window: daylight, colour, reflection on both sides and the evening view. Mention Low-E coatings, insulated-glass construction and any damage. Confirm the product, installation side and suitability against its documentation. For an initial quote, send photos, individual pane dimensions and access details.