A heavy duty Grandmaster workshop shed with fully braced wide double doors, opening windows and double glazing as standard. Available in a wide range of sizes.
The Heavy Duty D1000 is a pressure-treated workshop shed built for serious storage and DIY use, with fully braced wide double doors for easy access. Side-hung opening windows and double glazing are included as standard, with an extra strong double-sided roof truss for durability. Extra tall eaves and ridge height plus pre-assembled modular panels make it a spacious, easy-to-build workshop for any garden.
Prices as per the live configurator. Paint/trim swatch colours are indicative approximations.
For a stronger and longer lasting building with engineered interlocking cladding.
Tall, wide doors with thick timber bracing for better access and security.
High eaves and ridge make the interior feel like a proper workshop, not a garden shed.
Pressure-treated against fungal decay and rot, painting required annually.
Traditional apex roof with green mineral felt as standard.
Flatpacked and fits through a standard UK door with all fixings included.
No hidden extras and no surprise add-ons. Your Garden Workshop arrives complete — every panel, fixing and fitting ready to go.
Factory-applied before it leaves us, at no extra cost.
Upgrade from 11mm to 16mm tongue and groove shiplap for an even stronger wall.
Tongue-and-groove floor and roof for a solid, tight build.
Double glazed windows included as standard.
Every fixing and fitting included as standard, with premium quality throughout.
Pressure-treated against fungal decay and rot. Painting required annually.
Stage-by-stage illustrated instructions with all fixings included.
We offer free UK delivery on selected postcodes.
The Heavy Duty Workshop Shed is built for people who actually use their shed. Fully braced wide double doors, opening windows as standard, double glazing throughout, extra tall eaves and a range of sizes from compact to substantial. Pressure-treated and built to the same Grandmaster standard as the rest of the range.
Every Grandmaster panel is built on 27x44mm framing with key supports doubled to 54mm, giving the building a rigidity you can feel. Pressure-treated 11mm shiplap cladding with a 16mm upgrade option, an 11mm T&G roof on heavy-duty purlins and mineral felt covering as standard, backed by a 25-year anti-rot guarantee*. Built properly and treated annually, this is a building that will give you years of enjoyment.
27x44mm panel framing with key supports doubled to 54mm, plus an extra strong double-sided roof truss. Pressure-treated 11mm shiplap with 16mm upgrade option, green mineral felt as standard and a 25-year anti-rot guarantee*.
Your Garden Workshop arrives as pre-assembled, pre-insulated panels — designed to fit through a standard UK doorway and slot together with far fewer parts than a traditional log cabin. A quicker, simpler build, whether you do it yourself or bring in help.
Every building includes clear, step-by-step illustrated instructions. We recommend two people with basic DIY know-how — or add our assembly service at checkout and we'll handle it for you.
Add assembly at checkout →
Choose 11mm or 19mm tongue and groove floor to suit how you plan to use the building.
Choose 11mm tongue and groove shiplap as standard, or upgrade to 16mm for a more substantial build.
Green mineral felt as standard. Upgrade to EPDM rubber roof for longer protection.
Add guttering to manage rainwater runoff and protect the base of your building.
High-quality paint supplied in a tub. Apply after assembly to colour and protect the timber.
Optional timber base frame for use on firm, level ground if you don't have an existing concrete or paved base.
Built around how you use it, with options to make it exactly right.
| Overall Width | 253 cm |
| Overall Depth | 229.2 cm |
| Total Wall Thickness (incl. insulation) | 80 mm |
| Width (internal) | 229 cm |
| Depth (internal) | 174.3 cm |
| Eaves Height (inc. floor) | 230.7 cm |
| Eaves Height (excl. floor) | 218.2 cm |
| Ridge Height (inc. floor) | 240.2 cm |
| Ridge Height (excl. floor) | 227.7 cm |
| Eaves Height (internal) | 204.4 cm |
| Ridge Height (internal) | 212.4 cm |
| Door Height | 180 cm |
| Door Width | 73 cm |
| Door Opening (H × W) | H180 × W73 cm |
| Glazing Thickness | 4–20–4 mm |
| Frame Thickness (H × W) | 2.7 × 4.4 cm |
| Overall Floor Size (W × D) | 249 × 194.3 cm |
| Base Size | 244 × 189.3 cm |
| Cladding | 9mm LP Strongcore composite |
| Floor material | Tongue & groove |
| Roof material | Galvanised steel & foam insulation |
| Roof covering | Galvanised steel |
| Glazing | Double glazing |
| Building type | Garden room |
| Windows | 4 |
| Roof style | Pent |
| Cladding style | Composite board |
| Locking system | UPVC multi-point |
| U-value, metal roof | 0.49 W/(m²·K) |
| U-value, walls & floor | 0.31 W/(m²·K) |
| Pre-assembled panels | Yes |
| Interchangeable windows | No |
| Fixtures & fittings | Yes |
Dimensions shown for the 8 × 6; imperial values are converted from metric. 15-year anti-rot guarantee on composite — annual treatment required; terms apply.
Free delivery to selected postcodes, and Made in Britain.
"Genuinely warm in winter — I work in here every day now. Build quality is excellent."
"Panels went together far faster than I expected. The composite finish looks premium."
"From order to install was seamless. The team kept me informed the whole way."
British-made garden buildings, designed and built in Nottinghamshire.
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