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Vantage 350 Modern Summerhouse

Approx. W3.5m x D3m / W11'6" x D10'

(Sizes shown are approximate & full sizes are shown in the product specification)

From £2,069.99 £2,224.99
Save £155
Free delivery *
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  • 4mm toughened glass. NOT cheap styrene
  • Strong cylinder lock for security
  • Sturdy 19mm tongue and groove roof and floor
  • Designed with the DIYer in mind for quicker install

Vantage 350 Modern Summerhouse Overview

Our summerhouses have a specification far better than any competitor. This modern summerhouse features large purlins for extra roof strength, secure locking French double doors, and large windows with unique Dunster House domestic hinges. Unlike some competitors, we use 4mm toughened glass, not shed spec glazing or plastic alternatives. We also include pressure treated floor bearers which the summerhouse will sit upon.

Key Features

  • Full length logs, Not mixed or finger jointed
  • Slow grown Spruce, not cheap Pine. Built to last!
  • 10 Year guarantee on pressure treated floor bearers
  • All fixings included at no extra cost

Additional Information

To ensure the very best quality, we only use slow-grown White Spruce Timber, which is harvested in cold climates to ensure solid, dense log rings. This gives the wood superior strength and longevity, and also a much more consistent colour than the likes of Pine.

Despite the care we take in selecting the very best Timber available, it’s not like predictable brick or cold steel, this natural material has characteristics and quirks unique to every log.

Because our timber logs once fed water and nutrients back and forth from its roots to its leaves, its very nature is to be porous and swell up when it gets wet. Any wooden product will do this throughout its life, but there are a few things you can do to help limit this movement.

These include:

1. A great design!

  • Don’t worry, we’ve got this one covered. We’re experts when it comes to all things timber, so we have designed our products from the ground up with its natural properties in mind.

2. Water Repellent Treatment.

  • How you customise and decorate your product is up to you, however we would recommend that you use an appropriate water repellent treatment. This really helps minimise the amount of moisture that the timber can absorb. Therefore minimising the risk of any major movement.
  • (Please note: water repellent treatment is not the same as pressure treatment, which protects against rot and insect infestation, and which we guarantee for 10 Years!)
  • On pressure-treated timbers, you may notice some subtle striation marks. These marks sometimes appear during the drying process of timbers. Fear not! In time, the marks will begin to fade as the sun starts to lighten the wood.

Timber with Striation marks

3. Ventilation.

  • Keeping your timber building ventilated is no less important than keeping your house well ventilated. This is especially true if you plan to cover up your floorboards with something (double check with an expert, that the material is suitable to do so), as moisture can become trapped between layers of non-breathable materials and build-up, leading to floors becoming rotten.

4. Regular Seasonal Maintenance.

  • Whether you opt to build your product yourself, don’t be afraid to tighten the odd bolt here and there. Your product is a life improving investment, so it’s only right to give it some love and care from time to time. Make sure that it’s properly treated before the rainy months, and you make adjustments to doors and window frames, when needed.

Natural Timber Properties

After building your timber product, this natural construction will begin to ‘settle’. This means that you will likely see some natural timber imperfections appear. These types of natural imperfections can include:

Cracks

Cracked climbing frame timbers

Splits

Split Timbers

Shakes

Timber Shakes

Warping / Twisting

Expansion and Contraction

Please be aware that, as these are natural timber properties they are not considered as defects under our Terms & Conditions (for more information, check out our Terms and Conditions. However, in most cases, these imperfections will not impact the integrity or function of your timber product, and/or can easily be rectified. For advice on how to rectify these and for more support, please get in touch with our Customer Services Team on [email protected].

Unlike our competitors, we only use high-quality spruce timber on our wooden products rather than cheap pine or mixed timber. Why do we use slow grown spruce rather than the much cheaper knotty pine alternatives?

Spruce is considered more stable as it expands and contracts less than pine. This stability means that the spruce timbers in our garden buildings minimise splits from appearing as the timber changes along with the weather.  We responsibly source all our timber, where it grows slowly in the cold northern regions. We all know the old adage of counting the rings to see how old a tree is, well our timber grows slower and takes longer to get to size meaning it has more rings in it. This means it has a tighter grain, and each ring helps prevent cracks and shakes from appearing in the densely packed timber.

Our wooden garden buildings and climbing frames really are built to last therefore we use only the highest quality, slow-grown spruce.  Spruce is much more resilient to warps and splits compared to its cheaper alternative pine. Being a whitewood, it doesn’t discolour anywhere near as much as pine so it is also much more aesthetically pleasing for a garden structure. Considered more stable, less knotty and resinous than pine, spruce will also produce a lot less sap. It is also less dense meaning it is not as susceptible to mould and rot.

Outdoor Living Slow Grown Spruce

Outdoor Living Slow Grown Spruce II

This garden building is under 2.5m high. Why does this matter? Under permitted development rights, buildings under 2.5m high can be placed as close as you want to a boundary (eg. a fence line) without planning permission. Garden buildings that are over 2.5m high need to be placed over 2m away from any boundary (eg. a fence line), which could lead to a lot of wasted space. If you want to find out more about permitted development rights see our planning guide

Both our doors and windows are fitted with internal beading used to secure the glazing in place. This beading style is typically found in uPVC windows and is a proven method of security. However, there are still some companies that externally bead their windows. Allowing intruders to remove the glazing from the outside of your garden house and gain access.

internally beaded windows

We only use full lengths of timber in our garden products – we don’t glue separate offcut pieces together with finger joints. Not only are they stronger, but they look much better too.

Other companies are happy to provide you with rough offcuts, mixed timber and finger jointed timber, creating an odd-looking weak garden building with an off-putting appearance.

No Glued together Offcuts Good

We don't use Glued together Offcuts

The bearers of your garden building are pressure treated to help protect your garden building from the ground up. We provide a 10 year guarantee against rot and insect infestation for all pressure treated timbers.

Unlike some competition, we can offer a genuine 10-year guarantee against wood-eating fungal and insect infestation on pressure-treated timber.

All our Pressure Treated timber is for Use Class 3

10 Year Guarantee on Pressure Treated Timber

There is nothing more annoying than being in the middle of building something and finding that you don’t have the right fixings to continue. We include all of the screws, nails and fixings that you will need to put your garden building together – not many of our competitors are that thoughtful. This eliminates the need to worry about the type of screws or the length of nails you might need to get started – it’ll all be with your delivery.

Fixings Included

The 16mm shiplap walls come in panels, so each piece of timber is cut to size. These panels are easy to slot in-between the solid 60mm or 86mm corner posts, making the construction of your summerhouse quick and simple, almost like a giant jigsaw puzzle.

Easy Build DIY Summerhouse

The high internal eaves (1.94m/6’4″) give a spacious, light and airy feel once you’re inside. This is the lowest point of the roof which quickly rises, giving plenty of headroom for all of you over 6’4″!

High Internal Eaves

Our summerhouses have robust 70mm x 35mm roof beams, which are reinforced by additional supports at the sides of each roof panel. With the metal spider brackets this gives a very strong roof structure to make sure that roof sagging is an issue that will only be suffered by the customers of companies that supply lesser products.

Heavy Duty Roof Purlins - Summerhouses

Our windows and doors come with optional sculpted Georgian bars that sit firmly against the glass, rather than float in front of them. When applied to the windows and doors they add a traditional, elegant charm to your cabin. The Georgian bars are easily removed for maintenance, or if you decide you prefer the look of the building without them.

Georgian Bars for summerhouses

A strong cylinder lock will help keep your summerhouse secure. It’ll keep your belongings safe from unwanted visitors, and it’ll stop the kids from messing up your relaxation space.

Cylinder Lock

The solid and dependable 86mm thick chunky corner posts have a truly formidable outside appearance of 145mm x 145mm. This coupled with the 45mm thick framework either side makes our summerhouses very sturdy, with a substantial look and feel.

16mm Shiplap Timber 16mm Shiplap Timber

We use 4mm thick toughened glass, not Perspex or Styrene which can scratch easily and cloud up over time. This is also thicker and less likely to break when hit with the neighbour’s pesky football compared to the industry standard of 3mm horticultural glass.

Toughened glass Not cheap styrene

Toughened glass Not cheap styrene

All of our garden buildings have pressure-treated floor bearers as standard. This treatment prevents the timber bearers from rotting for up to 10 years and causing your garden building to sink. Pressure treatment forces the wood preservative into the timber rather than simply dip treating (essentially just covering the exterior) like many companies still do. Who wants to have to annually deconstruct and re-treat the bearers each year!

Due to this costly but effective process, we can offer our customers a genuine 10-year guarantee against rot and insect infestation on the bearers.  We do however recommend applying a good quality water repellent to the timber to prolong the longevity of the timber. Shockingly many of our competitors still offer untreated bearers to keep their costs down, so beware!

All our Pressure Treated timber is for Use Class 3

Pressure Treated Bearers

Rotten Untreated Floor Bearers

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Shiplap cladding is named after the old boatmaking technique with overlapping boards, which means that the natural timber can expand and contract with the seasons and not create gaps. The curve or channel of shiplap cladding enables water to run off easily, helping to protect your Summerhouse from the effects of damp.


We only use 4mm toughened glass in our Summerhouses which is a far more hard-wearing and resilient material than commonly used Perspex and styrene.


We use slow-grown spruce timber for the main structure of the Summerhouse. Spruce is less porous than Pine and so less likely to shrink, warp or split.

 

It is 2.45m (8' 0") high

 


A Summerhouse is a garden building made from pre-fabricated timber panels attached to a timber framework. Summerhouses also include several long windows, allowing large amounts of sunlight to fill the garden building.

No, we do not have any showrooms or display sites. All business is completed online and via our website. If you do have any queries that haven’t been answered with the information provided online, please feel free to call our sales team on 01234 272445.

We recommend a flat, level base at least 100mm bigger on each side. e.g. A W4.0m by D3.0m garden building would have a base of 4.2m by 3.2m See more details here.

Often, an additional cost is buried within the price when offering finance, thus making your purchase higher priced. This is the reason we do not offer finance and feel that it would not be beneficial for our customers or us. However, we have come up with an alternative method for you where you can use a 0% interest-free credit card to pay off your purchase. For more information, see this article: Do we offer finance?

Dunster House commit to continuously improve the sustainability level of our sourcing, by favouring stricter more credible certification and verification standards, and sourcing requirements. We are committed to avoiding sourcing from unknown or unsustainable sources.

Where possible, Dunster House are committed to procuring wood products that have been certified against credible, internationally recognised standards for good forest management, to ensure that material originates from well managed forests.
In line with this, we preference products certified to the standards of FSC (Forest Stewardship Council) and PEFC (Programme for the Endorsement of Forest Certification).

What about illegal timber?

Dunster House are committed to sourcing only material that is produced, processed and traded according to applicable legislation.

What is your Environmental Responsibility policy?
Dunster House are committed to promoting responsible stewardship of the environment and its natural resources. We are committed to lessening the impact on the environment caused by our own activities, and those of our suppliers.

Do you have a Supply Chain Management policy?
Dunster House will ensure that information about suppliers and material is gathered as part of the RPP. We will ensure regular engagement with our suppliers to ensure compliance with UKTR requirements, working with them to ensure continuous improvements. We will also specify that, wherever possible, that material sourced is covered by FSC and PEFC, to ensure responsible forest management.

Yes, we do! Some postcode restrictions do apply however we are pleased to be able to deliver to many parts of Scotland.

For more information – Where Do We Deliver?

We do not currently offer installation. All our garden buildings have been designed on the basis that any competent DIY customer will have no problem installing a product themselves in a short amount of time.

You do not have to be an expert at DIY to build a Dunster House garden building, as we do provide you with comprehensive pictorial instructions. Also, if you prefer video tutorials, we do have a selection of videos on YouTube which will support you in building your product.

We totally understand that DIY is not for everyone and it can be very overwhelming to start building your own garden product. Therefore, you may want to consider getting in touch with a local carpenter or handyman to install it for you.

If you do take on the challenge to put your garden building together, we are always here to help. Do not hesitate to contact us at any stage of putting your product together and we can provide you with all the assistance you may need. Contact our customer service team via email at [email protected].

Due to the unique design of a Dunster House product, in the vast majority of cases our garden buildings can be installed without the need for planning permission.

However, there are a few other factors to consider:

As all properties are different in size, shape and style we can only advise based on how we have designed our products, not on your property.

When to consider planning permission:

  • If the garden building exceeds over 2.5m tall – the majority of Dunster House buildings do not exceed this.
  • If you intend on putting an outbuilding in front of the main elevation of your property (as it was originally built or as it was on 1st July 1948) will require Planning Permission.
  • If you live in a listed or graded building
  • If you live in a designated area such as areas of outstanding natural beauty, national parks, world heritage sites and conservation areas.
  • If there is a possibility that over 50% of your garden would be taken up by outbuildings.

Click here for more information on Garden Building Planning Permission in the UK.

Still not sure?

If you are still in doubt, we highly recommend getting in contact with your local authority before making a final purchase.

We offer a genuine 10-year guarantee against rot and insect infestation on pressure treated timber, which covers the floor bearers of your product.

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Vantage 350 Summerhouse
  • Please Note: All sizes quoted are nominal
  • External Width: 3.50m (11' 5")
  • External Depth: 3.00m (9' 10")
  • Internal Width: 3.30m (10' 9")
  • Internal Depth: 2.70m (8' 10")
  • Internal Area (m2): 7.25m2
  • Ridge Height: 2.45m (8' 0")
  • Internal Eaves Height: 1.97m (6' 5")
  • Roof Overhang: 362mm (1' 2")
  • Roof Thickness: 19mm Tongue & Groove
  • Roof Covering Options: None, Felt or Shingles
  • Walls: 16mm Shiplap
  • Floor Thickness: 19mm Tongue & Groove
  • Floor Bearers: Pressure Treated for Longevity
  • Door Style: French Doors, Fully glazed
  • Door Locking System: Cylinder Lock
  • Door Walkthrough Height: 1.70m (5' 6")
  • Door Walkthrough Width: 1.05m (3' 5")
  • Windows: 2 French style Opening
  • Window Opening Size: 0.50m x 1.48m (1' 7" x 4' 10")
  • Glazing Material: 4mm Toughened Glass
  • Georgian Bars: Included - optional to fit
  • Timber: Spruce
  • Approx. DIY Assembly Time: 1 - 2 Days* *This is an approximate time only, based on 2 people. Assembly time may vary depending on season/weather conditions, foundation type, ability of those constructing, etc
  • Please Note: All fixings needed for assembly are supplied
  • Please Note: All wood is planed and pre-cut (with the exception of trims), for quick and easy construction.
  • Please Note: This Summerhouse arrives at your door untreated. We sell a range of suitable coloured timber treatments (supplied in tins).
  • Please Note: Friction stay colours may vary between black and silver

Vantage 350 Modern Summerhouse Ratings

R Caygill

Very professional and efficient company.

Very professional and efficient company.

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Cable Fork & Truck Services Lt

DHappy customerelivered on time

Delivered on time, no parts missing and our team put it up first time. A very good product and we are pleased we bought it.

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Cable Fork & Truck Services Lt

DHappy customerelivered on time

Delivered on time, no parts missing and our team put it up first time. A very good product and we are pleased we bought it.

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Janet Stevenson

Excellent and efficient company to deal

Excellent and efficient company to deal with. Beautiful products. Bought summer house and very pleased.

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Delivery Information

* Free delivery on orders over £200.

We deliver our products to mainland United Kingdom (England, Wales and most of Scotland). Some exceptions apply; these are illustrated on the map below.

Postcodes affected include:

  • TR
  • TQ6, 7, 8, 9
  • EX19, 20, 21, 22, 23, 38, 39
  • LD
  • PL10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35
  • SA
  • KW
  • HS
  • ZE
  • KA27, 28
  • IV1, 4, 6, 7, 8, 9, 10, 11, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 63
  • PA20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 80
  • PH32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44

Dunster House delivery map

Green – Free Assisted Delivery

Red – We are unable to deliver to these areas.

Purple – For orders to Ireland & Northern Ireland, please visit our Distributor in Ireland here.

Delivery Service

All of our products are delivered using our own fleet of vehicles, not sub-contractors. We have a large number of vehicles dedicated to delivering our quality products so we can guarantee maximum care is taken during the delivery process.

Our deliveries take place Monday to Friday between the hours of 8:00 am and 6:00 pm.

When the delivery vehicle is unloaded, it is important that you check to make sure all of the items and instructions have arrived and are correct. You will also receive a component list to check your items against. If anything is missing or damaged, it is essential that you note this on your paper work when you hand it back to the delivery driver.

Prices for our delivery services can be found on individual products.

Please note that goods will be delivered to the first point of contact at the front of your property e.g. on your driveway. This must be within 20m from the delivery vehicle (Safely Parked at Kerbside). Our team will be responsible for assessing the risk of carrying out delivery upon arrival at the property.

Should you require further information on our assisted delivery services, please click here to read our Terms and Conditions, alternatively you can contact a member of our Sales Team.

See the locations we deliver from.

Q: Where can I find more information?

A: If you have any questions regarding your delivery, you can telephone our Dispatch Team. Contact details for the Dispatch Team of your nearest branch can be found on your order confirmation. If you need to track your delivery or access your manuals in advance of your delivery, you can visit the Customer Log-In Area of our website.

Thank you for taking the time to read about our terms and advice during this period. We hope you can enjoy your Dunster House garden product for many years to come.

Why Buy From Us?

Buy with confidence! Established for over 30 years, you can rest assured of our knowledge and experience as industry leaders.

On pressure treated timbers*. We don’t dip-treat our timber unlike some competitors. Dip treatment isn’t as effective at protecting against rot and infestation!

All products are uniquely designed and of high quality with many industry leading features you will struggle to find anywhere else!

A UK company and family run business. Our products are designed  and distributed from our 11 UK distribution centres.

Many have bought from us over the last 30+ years due to our superior specification and the fact that our products are designed with the DIY market in mind.

Free delivery on most products*. Delivered to you by our own fleet of vehicles and dedicated drivers.

Inspiration/Customer Stories

Dean’s Garden Cinema Room

View Case Study

Ed’s Garden Music Room and Home Office

View Case Study

Andy and Rose’s Garden Games Room

View Case Study

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† Reference to Price on 22nd December, 2023

Vantage 350 Modern Summerhouse

From £2,069.99 £2,224.99
Save £155