Description
The Over Sill White 2.5m 170mm Depth carries a window sill out over the face of an insulated, rendered wall: one 2.5 m length of white profile at 170 mm depth, the third of four. It belongs to the white trim family of the oversill range, sold alongside the matching verge trim and end caps.
The Over Sill White 2.5m 170mm Depth Profile
The product image shows a flat sill board with a short upstand along its back edge and a front edge turned down, pictured with an end cap fitted at each end. The same image stands on all four white depths, so it shows the shape of the family, not the 170 mm size. The listing gives three facts about the item:
- Length: one 2.5 m length.
- Depth: 170 mm, the third of four depths in white and the second deepest.
- End caps: the title names the profile only, and the range sells the caps as their own item, the white end cap pair, listed for the sill profiles and the verge trim of the same colour.
Four Depths in White
The same white profile is listed in four depths, all on the 2.5 m length, and 170 mm sits between 140 mm and 220 mm. The other three are:
- 110 mm: the 110 mm white over sill, the shallowest of the four.
- 140 mm: the 140 mm white over sill, one step shallower than this one.
- 220 mm: the 220 mm white over sill, one step deeper and the last of the four.
The listing does not say what the depth is measured across, or which wall build-up each depth is made for. Sitting between two depths does not make 170 mm the safer pick when a wall falls somewhere in between: the right depth comes from the wall, not from the middle of the list.
Settling the Depth Before You Order
No build-up is named for any of the four depths, so the depth is settled with the counter. Two measurements from site make that a short call:
- The new build-up: the thickness of insulation and render going onto the wall at the opening, measured on site rather than taken from the drawing.
- The existing sill: how far the current sill stands out from the wall face today.
Ring Renders World on 023 8200 2442 with both figures and settle the depth before the order goes in. Where the openings on one elevation differ, give the figures for each.
How Many Lengths and Caps an Opening Takes
Measure each sill and divide by the 2.5 m length, rounding up: a 1.8 m opening takes one length cut down, and a 3.2 m opening takes 3.2 ÷ 2.5 = 1.28, so two lengths. Then count open ends, not lengths:
- One opening, two open ends: one end cap pair, however many lengths the sill is made of.
- Several openings: each separate sill with two open ends takes its own pair.
- Openings wider than 2.5 m: the range lists no joint piece, so settle how two lengths meet with the counter before ordering.
The White Trim Family
The sill profiles belong to one colour family. In white the range also holds:
- Verge trim: the white verge trim with an upstand, for the top edge of the wall.
- End caps: the white pair, listed for the sill profiles and the verge trim.
Each end cap pair is sold for the trim of its own colour, so a white sill takes the white pair.
White or Anthracite
The 170 mm depth is listed in two colours, and the colour of the scheme decides:
- White: this profile, with the white verge trim and the white end cap pair.
- Anthracite: the anthracite 170 mm over sill, with the anthracite verge trim and the anthracite end cap pair.
Fitting the Over Sill
The listing gives no fixing method, sealant or sequence for the profile. Two guides cover the work at the openings:
- The sill profiles: measuring, cutting and closing runs, in the guide on how to install window sill extensions.
- The openings: how sills, beads and render meet, in the guide to render detailing at door and window openings.
Ordering, Delivery and Returns
Renders World processes orders the same day when the stock is there. Put the end caps in the same basket as the lengths they close.
- Delivery: quoted by the team after the order; parcels up to 25 kg go next day, always kerbside.
- Collection: from the counter at Unit 9A, Central Trading Estate, Southampton SO14 5JP, Monday to Friday 7am to 5pm and Saturday 7am to 12pm.
- Returns: goods bought directly from Renders World can go back within 14 days in their original condition; special orders and promotion purchases are excluded.
FAQ
Which insulation thickness does the 170 mm depth suit?
The listing names no build-up for any of the four depths. Ring 023 8200 2442 with the insulation and render thickness and the current sill projection before ordering.
Does the picture show the 170 mm profile?
It shows the white profile's shape. The same image is used for 110, 140, 170 and 220 mm, so go by the depth in the title.
Is the profile aluminium or uPVC?
The listing names no material, coating, colour code or thickness. Where the material matters to the specification, ask the counter before ordering.
Is it an internal window board?
No. It is an external profile, sold in one range with a verge trim and end caps, and it carries the sill out over the face of an insulated, rendered wall.
My wall falls between 140 and 220 mm. Is 170 mm the one?
Not by default. No depth is matched to a build-up in the listing, so give the counter the two site measurements and settle it before ordering.
Is the 170 mm depth sold in anthracite?
Yes, as the anthracite 170 mm over sill, with its own anthracite end cap pair.

