Picture windows made to measure

That doesn't depend on the section but on the profile and on the glass. The maximum size per profile is on the profile page; the configurator checks it and refuses a size that goes over it. With large fixed areas the limit is not the frame but the weight of the pane — which can get considerable with triple glazing.

Structurally, usually yes, but look at the ventilation of the room first. Building rules set requirements for the fresh air supply of a habitable room and for purge ventilation — the ability to push a lot of air through it in a short time. A fixed light provides neither: it gives light and no air. If the window you are replacing is in a bedroom or a kitchen and it is the only opening, the room's ventilation goes with the sash. If the home has mechanical ventilation with heat recovery, the supply is often already arranged and it is less likely to be a problem. In other cases you solve it with a trickle vent or with a narrow tilt and turn section beside it. We don't check that for you — we make the section to the size you give. What exactly your situation needs is a question for your installer or building control.

No. A sash needs its own frame, and a fixed light doesn't have one. If you are unsure, choose a fixed sash: that is a sash frame without hardware, so the same sightline as a tilt and turn window but closed. More expensive than fixed glazing, cheaper than tilt and turn.

From outside. On the ground floor with a squeegee, higher up with a telescopic pole or a window cleaner. Count on that before you order a floor-to-ceiling fixed window on the first floor — it is a recurring cost nobody includes.

uPVC is the cheaper of the two and technically loses nothing with a fixed light. You choose aluminium for the look: a sightline from 89 mm against 119 mm, and with a fixed light that has no sash frame anyway, that gives the largest area of glass we can make. With large areas, by the way, the limit is not the profile but the weight of the pane.

The **outside size of the frame**, the same size we supply to and that the size guarantee applies to. With a fixed light this gets misread more easily than with an opening window, because there is no sash to make the difference visible: what you see is glass with an edge round it. The size you measure on site is often the **structural opening**, and that is not the order size. Work back to the frame size yourself and keep the fitting gap you want; we don't install and so can't choose that gap for you. We supply within ±2 mm up to a metre and ±3 mm above that and measure every unit before dispatch; the measurement sheet goes with the order confirmation. If the size you gave doesn't match your opening, that is outside the guarantee — there is a second chance at cost price for that.

We don't know, and that is why we don't say so. KOMO is a Dutch quality mark; it attaches to the manufacturer and its production line, through an attestation with product certificate and periodic inspection — for uPVC window and door units via BRL 0703. We buy from five manufacturers and hold a certificate number from none of them. As long as that is the case, we don't write anywhere that our windows are KOMO-certified. If you need it for a specification or an insurer, ask us before you order.

With the same profile and the same glass, a fixed light tends to insulate slightly better: there is no gap along a sash, only a continuous rubber seal around the glass. The difference is small compared with the choice of glass itself — triple glazing instead of HR++ double glazing (Ug 1.1) makes far more difference than fixed versus tilt and turn.

Yes, that is exactly what many front doors with a side panel come down to: a door section with a fixed light beside it in one frame. For that kind of configuration, look at the front door page; here it is about the fixed light on its own or beside a window.