Planning is probably the most important issue to get right with decking to ensure good results. Select the location of your deck carefully, having regard for privacy and sun, shade or wind. Decks built in highly shaded positions will require more regular maintenance.
Consider the nature of exit and entry to the building - make sure you allow access to the decking from existing doors and steps, and tie in the deck to any existing walkways that you may wish to retain.
Keep the size of the deck in proportion to the building and exterior. In England new planning rules now apply to the size of decks in relation to an existing property or garden. For example, surfaces (including decking) are not permitted to cover more than 50% of a property’s garden.
For all but a simple, ground level / patio style deck, property owners should satisfy themselves as to whether planning regulations apply to their proposed structure. Since 1st October 2008, planning permission is now required where a deck platform is more than 300mm (1ft) from the ground.
If unsure, the property owner should always first discuss their intentions with their neighbours and the Local Authority planning office.
Where there is a higher than normal requirement to prevent the risk of slipperiness, for example on ramps, stairs, bridges or on public / commercial installations, then it is necessary to consider deck boards that have enhanced grip characteristics, such as Hoppings' Q-Grip®.
Situations requiring planning permission:
- Where the deck is situated within 20 metres of a highway.
- Where the deck platform is more than 300mm (1 ft) from the ground.
- If any part of the deck construction exceeds 3m in height.
- If the structure would affect the amenity value or privacy of neighbouring properties.
- If the deck is attached to a listed building or situated in a conservation area or National Park.
Consider the end use of your deck when planning the sub-frame design. You may need commercial specifications for large groups of people. For commercial pub and restaurant type decks it is wise to consider the use of fire-retardant treated sub-frame and deck board components and / or the use of deck boards with enhance grip characteristics.
Typical deck constructions include:
- Ground level
- Partially elevated
Choose the direction in which to lay the deck boards - this will establish joist direction. Deck boards with smaller cross sections need more joists and greater support.
When designing and building decks, always plan to achieve a free draining structure. For adequate water run-off, decks should be laid on a slight gradient (at least 1 in 80). Lay grooved decking down the fall to enable run-off and ensure the groove ends can drain freely. It may be necessary to pack out the fascia.
Laying deck boards in checkerboard or quadrant patterns can hinder drainage and will require more regular maintenance.
If the deck is attached to a dwelling wall, the finished deck height should not compromise the damp proof course (DPC). With 'old' houses it is advisable to keep the deck height at least two brick courses below the DPC.
If the design means the deck will cover a manhole or other services, ensure that there will be a removable panel into the surface to give easy access in the future.
Balustrades (or parapets) on decks can serve several functions, ranging from simple decorative boundaries to full safety barriers. Even a small change of level can be a hazard, particularly for elderly or infirm users. Unless the deck surface is flush with its surroundings, a ground level, parapet or edge protection detail should be incorporated. For very low-level structures, this may take the form of a simple decorative rail, a lattice panel or a raised planter.
The height of the balusters and handrail depends on how far the deck surface is off the ground. For 'low level' decks up to 600mm from ground level, the height should be 900mm. For 'high-level' decks over 600mm high, the height should be 1100mm.
Hoppings' Q-Deck® Plus strength rated balustrade system is designed to meet Building Regulation requirements for outdoor use. It can be used in areas where people may congregate, such as restaurants.
Hoppings provides technical information such as quantity advice, joint spacing tables, and joist and beam span tables.
Beams, for example, are recommend to be constructed from two 44 x 145mm Q-Deck® deck joists placed at maximum centres of 1.8m.
Hoppings also provides one-to-one technical assistance on a specific project basis.
Hoppings can provide design recommendations to minimise the risk of fungal decay and insect attack, and thus simplify a warranty claim.
The company's Q-Deck® components are preservative pre-treated to different levels of protection to the meet the requirements of industry standards.
- Class 1: Internal building timbers with no risk of wetting or condensation.
- Class 2: Internal building timbers with a risk of wetting or condensation.
- Class 3: External building, fencing and landscaping timbers, out of ground contact.
- Class 4: External building, fencing and landscaping timbers, in ground contact.
Use Classes are defined by British and European Standards, providing a guide to the risk of decay or insect attack to timber components, depending upon their end use. The higher the Use Class, the higher the level of preservative protection is required.
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