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If you are not completely satisfied with your purchase, you have 30 days from the purchase date to return the item(s) back to us for a refund. Please note: £3.50 will be deducted from the overall refund amount.  


Forest Garden Xtend Premium 4.0m

As low as £12,399.99 RRP: £12,648.99
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Achieve your work/life balance with the Xtend range of garden buildings from Forest Garden. These new buildings have everything you could wish for in a home office - contemporary looks, real energy efficiency, ease of construction and keen pricing. Space is at a premium in most homes and extensions are costly. An Xtend garden building is constructed from high quality, energy efficient materials and is underwritten with a 15 year structural guarantee Xtend is a clever choice for your garden building as it comes delivered in pre-cut modular SIP panels ready for assembly. Some of the best designed new homes are now made this way, so why not your new garden building? A step-by-step guide means the build is incredibly straightforward. Keeping you warm in winter and cool in summer, Xtend delivers real energy efficiency. Double glazed windows, highly efficient insulated walls, roof and floor combine to drive down energy costs. It’s a fact that Xtend garden buildings can be as energy efficient as a new-build home – with an EPC energy rating of B. All fixtures, fittings and step-by-step instructions included
Please note: Delivery for this item will take 4-6 Weeks Uninstalled and 6-8 weeks Installed
Please see below for postcode areas which have an extended lead-time of up to 7 working days beyond the advertised lead time.
All lead times can be found on each individual product. BN1-BN3, BN5-BN18, BN20-BN27, BN41-BN45, BR8, CB1-CB4, CB6-CB8, CO1-CO16, CT1-CT21, EX1-EX24, EX31-EX39, GU6, GU28, IP1-IP33, ME1-ME20, NR1-NR35, NE1-NE8, NE12-NE13, NE15, NE18-NE20, NE22-NE35, NE48, NE61-NE71, PE14-PE30, PE38, PL1-PL29, RH6-RH20, TN1-TN40, TQ1-TQ14, TR1-TR20, TR26-TR27

Deliveries to mainland Scotland can take up to 10 working days more than the advised lead times. .

We apologise, but Forest Garden do not deliver or offer an assembly service to the following postcodes:
BT1-BT99, GY1-GY9, HS1-HS9, IM1-IM9, IV41-IV56, JE1-JE5, KA27-KA28, KW15-KW17, PO30-PO41, PO49, TR21-TR25

* 250cm(h) x 404cm(w) x 342cm(d)
* The core structure of an Xtend building is made from SIPs panels - high performance material for building construction. The 21st century way to build
* 9 7mm thick insulated walls consist of 75mm of polystyrene insulation sandwiched by two sheets of oriented strand board (OSB)
* Gives structure and insulation in one pre-assembled and cut-to-size panel
* Total wall thickness including SIPS panels, internal and external cladding and cavities is 177mm
* Roof is 11mm OSB + 100mm insulation + 11mm OSB = 122mm total
* Pre-cut external timber cladding panels for quick and easy assembly
* No measuring and cutting every single batten and board to size before mounting
* Cladding panels are simply positioned on the building and screwed into place
* Panels are made with 15mm thick premium interlocking tongue and groove boards mounted to framing battens
* Comes untreated and we recommend the application of any of the following:c
Sikkens Cetol HLS Plus • Restol Wood Oil • Timmersol ETS Double Protectant • Osmo Country Colour • Osmo Natural Oil Woodstain
* Pre-cut interior MDF panels for quick and easy assembly for walls and ceiling
* No measuring and cutting every panel
* Wall panels are mounted to 28mm thick battens creating a cavity perfect for routing electrical wiring
* Roof battens are 45mm thick to allow for recess roof lights
* Comes with primer applied – can be painted in a colour of your choice using standard interior emulsion paint
* The panel design has a vertical beaded profile
* The floor is left unfinished for you to add your own choice of covering
* External roof covering is made from 1.2mm thick EPDM black rubber
* It creates a maintenance free waterproof membrane
* Does not crack, split or rot
* Does not support moss or algae growth
* UV stable & environmentally friendly
* Safe and easy to install – the system is laid with cold applied adhesives (supplied)
* One piece sheet means no joints and no leaks
* 50 years roof life expectancy
* Anthracite grey fascias include
* Window material: uPVC 5 chamber
* Window colour: Anthracite grey externally with grained finish Smooth white internally Window locking: Two double clasp, mushroom headed espagnolettes
* Door material: uPVC reinforced 5 chamber
* Door colour: Anthracite grey externally with grained finish Smooth white internally
* Door locking: 7 point multi-lock with ultion three star security barrel
* Glazing 28mm, A rated, double glazed, safety glass
* Highly efficient insulated walls roof and floor
* Double glazed windows
* Warm in Winter, cool in Summer
* Energy efficiency model rating of 78 (category C)*
* Potential to increase to 82 (category B) with the addition of a photovoltaic solar panel
(*based on lighting from 3 x 4 watt LED bulbs and heat from a high efficiency wall mounted heat pump)

Product Code - XTEND4.0


Express Delivery:
Free on orders over £50 & £5.95 for orders under £50

Tracked 24:
Free on orders over £50 & £4.95 for orders under £50

Tracked 48:
Free on orders over £50 & £4.50 for orders under £50

Click & Collect:
Monday - Friday 7:30am - 5:30pm & Saturday 7:30am - 5:00pm



If you are not completely satisfied with your purchase, you have 30 days from the purchase date to return the item(s) back to us for a refund. To create a return please head to the returns section of our website.


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