Casement
Side-hung or top-hung uPVC. Typical for side walls and small garden rooms.
CasementWindows & doors
uPVC to the opening. Priced on the quote
Casement, French doors, bi-fold. We do not list window SKU prices — sizes vary. Send opening sizes or pick a kit and we quote glazing with the package.
French doors
A pair of doors with side panels. Common on the garden elevation. Width quoted to your plan.
French doors
Bi-fold
Wide glass openings. Two sets of bi-folds shown here. Tell us if you want sliding, French or bi-fold doors.
Bi-fold
Sliding doors
Large glazed panels for a wide opening onto the deck. Tell us the opening width and we quote to suit.
Sliding and bi-foldWe supply the units. You or your builder form the openings in the SIP panels on site. No made-up U-values, no “from £399” windows, no stock photos of someone else’s house.
Windows and doors
Choose the opening
Casement windows
Side-hung and top-hung casements. Tell us width, height, opener side, and whether it sits in a 97, 122, 147 or 175 mm wall. Quoted. Not a finished install unless you ask.
See also: Design and quote · Project gallery
French doors
A pair of doors, usually on the garden side. Give us structural opening size. Threshold and cill details go on the quote. Quoted. Not a finished install unless you ask.
See also: Design and quote · Project gallery
Bi-fold doors
Three or more panes folding. Sliding is also an option. Say which. No catalogue price without a width. Quoted. Not a finished install unless you ask.
See also: Design and quote · Project gallery
Finishes and extras
Cladding
Hollow tongue-and-groove slatted WPC. Our price £35.35 per panel. No VAT to add. The price shown is the price you pay. Other cladding ranges below.
2.5 m slatted panel
£35.35 No VAT to add / 2.5 m panel
- Width 220 mm (200 mm lapped)
- Thickness 26 mm
- Length 2.5 m
- Coverage 0.5 m²
- Weight about 7.58 kg
- Hollow T&G, capped WPC, four-slat face
- Colours: walnut, teak, charcoal, stone grey, coffee, silver grey
- Walnut
- Teak
- Charcoal
- Stone grey
- Coffee
- Silver grey
No fire rating on this WPC slatted range. If the job needs a fire conversation, look at fibre cement below.
Trims and extras
| Item | Length | sipsonline — No VAT to add |
|---|---|---|
| Corner trim / start profile | 2.5 m | £23.54 |
| Internal / external / double end trim | 2.5 m | £3.75 |
| Sealant | Tube | £14.95 |
| Sample pack | Pack | £15.60 |
Battens, screws and perforated closures quoted with the take-off. 5% waste is normal — we will not hide it.
In use
Charcoal slatted. Outdoor kitchen
Same slatted range as the gym and the terrace room. Supplied through sipsonline. Colour on the quote.
In use
Slatted soffit. Composite deck
Dark slatted on the overhang. Deck and hot tub are extras, not a sipsonline room SKU. Supply of cladding and SIP panels. You or your builder fit.
Lifestyle
Slatted fence. Composite deck
Cladding and decking through sipsonline. Not a SIP product shot. Colour on the quote.
Other cladding
Same supplier, through us. From-prices: No VAT to add. The price shown is the price you pay. Ask for the current colour list and datasheet.
Supplied through sipsonline
Signature
£22.05
3.6 m composite. 157 × 21 mm, 0.45 m². Smooth from £22.05. Woodgrain from £28.24.
Supplied through sipsonline
ProClad
£30.80
3.6 m capped woodgrain. 157 × 22 mm section, 135 mm cover, 0.45 m².
Supplied through sipsonline
Fibre cement
£18.83
Lap from £18.83. Click from £25.20. 3.66 m boards. Use this if WPC fire rating is a no.
Finishes and extras
Decking and roofing
Full cladding, decking and roofing ranges through sipsonline. From-prices: No VAT to add. The price shown is the price you pay. EPDM is ours, quoted to the kit roof plan.
Decking
Colours include composite stone grey. Colour and board are confirmed on the quote.
Signature decking
£30.40
4 m Signature composite decking board. Colour and section confirmed on the quote. Trims extra.
ProDeck
£38.53
4 m ProDeck board, 143 × 23 mm. Capped composite. Ask about bullnose and grooved options; the from-price may not include them.
Metal roofing
Priced per metre. Length and colour quoted. 32/1000 and 34/1000 box profile, plus corrugated, tile form and standing seam on request.
| Finish (box profile, from) | Per metre — No VAT to add |
|---|---|
| Polyester paint / galvanised | £13.13 |
| PVC plastisol | £17.66 |
Flashings, fillers, screws and GRP rooflights quoted. Not a roofing labour price.
Cladding recap
| Range | Size | From — No VAT to add |
|---|---|---|
| Composite slatted | 2.5 m · 0.5 m² | £35.35 |
| Signature composite | 3.6 m · 0.45 m² | £22.05 |
| Signature woodgrain | 3.6 m | £28.24 |
| ProClad woodgrain | 3.6 m · 0.45 m² | £30.80 |
| Fibre cement lap | 3.66 m | £18.83 |
| Fibre cement click | 3.66 m | £25.20 |
Finishes and extras
EPDM
EPDM is quoted with the package. We size it to the roof plan plus upstand. Price depends on membrane size, outlets and trims. Metal roofing (profiled steel) is priced on the shop page if you would rather go that way.
Quote-led. Tell us the kit size (or roof plan L × W), upstand height, outlets / trims, and postcode. We quote EPDM with your SIP kit, sized to your roof.
Roof plan by kit
Starting roof plan from locked kit tables. Add upstand and waste on the quote — figures below are plan area only, not a finished membrane take-off.
| Kit plan | Roof plan m² |
|---|---|
| 2.44 × 2.44 | 6.0 |
| 3.66 × 2.44 | 8.9 |
| 3.66 × 3.66 | 13.4 |
| 4.88 × 3.66 | 17.9 |
| 4.88 × 4.88 | 23.8 |
| 6.10 × 3.66 | 22.3 |
| 6.10 × 4.88 | 29.8 |
| 7.32 × 4.88 | 35.7 |
| 7.32 × 6.10 | 44.7 |
12×12 ft headline ≈ 13.4 m² plan before upstand. Outlets, adhesive and edge trims are quoted. Metal roofing from £13.13/m.
Thickness & warranty language
Industry-common UK garden-room / flat-roof EPDM (public product pages — ClassicBond / Flex-R family and similar). This is sourced market context, not a sipsonline brand or warranty claim until the supplier is locked.
- Thicknesses commonly sold: 1.2 mm (standard) and 1.5 mm (premium)
- Membrane warranties (for example 10 / 15 / 20 year) typically need a trained / approved installer — not automatic because we supply a roll
- We do not print a sipsonline EPDM warranty number or named brand on this page until agreed
Prefer: EPDM quoted to roof plan. Prefer metal? Use the shop from-prices and still quote to length for your kit.
What we need for a quote
- Kit size or roof plan L × W
- Upstand height
- Outlets / trims wanted on the same drop
- Postcode (carriage)
- Whether adhesive / edge trims are included
Finishes and extras
Foundations
SIPS Online supplies ground screws with SIP kits. They replace concrete. No digging. They suit garden rooms and SIP extensions. Quoted with your package.
No digging
Screws go in on a 750 mm grid. You do not excavate a raft.
No concrete pour
They replace a concrete foundation on jobs that suit screws. Garden rooms and SIP extensions are the usual ask.
Quoted with the kit
Count, length and layout depend on the building and the ground. WhatsApp or the package form. No £/screw on this page.
With the kit
Screws, SIP panels, cladding
SIP panel walls on a timber floor frame, set on ground screws. Openings cut on site. We supply. You or your builder fit. Tick ground screws on the quote. London, nationwide.
Finishes and extras
Accessories
Panels ship recessed for timber joining splines. Splines and sealant are listed separately. Stock and exact SKU confirmed on quote.
| Joining spline (list) | £11 / £12 / £13 / £14 by size — confirm on quote |
|---|---|
| Sealant (list) | £14.95 |
List prices as published on the draft site. Tell us your panel thickness when you order so we match the spline.
Fixings, adhesives beyond listed sealant, and structural design are not included. See how SIP panels work and SIP kit inclusions.