Performance-led folding entrances
A “thermal” bi-folding door should be defined by the proposed frame, glazing, threshold, seals and declared system performance—not by the label alone. This category is for projects where heat transfer, weather exposure and internal comfort need to be considered alongside the flexible multi-panel opening.
What contributes to thermal performance?
- Frame construction and any thermal separation within the profile.
- Double or triple glazing build-up and edge spacer.
- Panel size, number of joints, seals and hardware adjustment.
- Threshold design, drainage and perimeter installation junctions.
- Quality of survey, manufacture, installation and commissioning.
Ask for the right evidence
If the project sets a thermal target, ask for the relevant declared information for the complete door set and confirm how it relates to the proposed size and configuration. A centre-pane glass figure is not the same as whole-door performance. The responsible designer or building-control adviser should confirm the requirements that apply to the property.
Panel layout and threshold still matter
Thermal performance does not replace operational design. Agree the panel number, stacking side, everyday traffic door, opening direction, threshold, weather exposure, drainage, glazing, hardware and finish. A very low threshold may have different weathering or access implications from another arrangement; the project team must choose the appropriate balance.
Use, care and adjustment
Multi-panel doors rely on aligned frames, hinges, rollers, tracks, locks and seals. Handover information should cover operation, cleaning, drainage, inspection and adjustment. Report dragging panels, damaged seals, water ingress or difficult locking before repeated use causes further damage.
Price and quote information
Opening size, panel count, frame system, glazing, threshold, hardware, finish, access, delivery and installation affect cost. Send the postcode, photographs, dimensions, panel preference and project thermal brief. The written quotation should state the actual system and performance information being offered.