Garden planning Hard landscaping Materials Natural stone looks good but is expensive, heavy (and therefore difficult to move) and of irregular sizes and thicknesses. It is also necessary to check its provenance – much stone sold today is imported from the Far East. Paving slabs are generally cheap but uniformly square and of even thickness. Timber decking works well near water – i.e. near a canal, in a coastal garden – or in a wooded area. Cobbles and setts are usually designed to nest together and can be used as flexible paving (laid directly on sand and not cemented in). Railway sleepers are reclaimed. Use to create raised beds or steps. To prevent the preservative from leaching into the soil, lay them on a piece of impermeable butyl pond liner. If you are using to make raised beds, line the inside with pond liner before filling with soil. If you need to cut sleepers to size, treat the exposed ends with a wood preservative. Bricks can be reclaimed. If they are in contact with the soil, they must be engineering grade (hence frost proof). They can be laid in patterns or used to edge or break up large expanses of paving. Concrete can be mixed on site and coloured to the precise shade needed. When planning a patio and choosing materials, try to create a design that avoids cutting them so far as possible. It is time-consuming (thus adding to the budget), wasteful and potentially hazardous. Saving money By far the largest part of the budget will be swallowed up by labour costs. These should be kept down as far as possible through careful planning. A major issue is the weight of materials and how they can best be moved around the site. Only as a last resort should they be brought through the house. Not only is this disruptive but only a small volume of materials can be carried through at any one time. Many houses have access at the side of the property or the rear. It can sometimes save time and money if a fence panel can be removed (particularly if the project involves replacing the fence). Materials should be stacked as close as possible to where they are needed. Health and safety Many hard landscaping materials are heavy and awkwardly shaped. Cutting tools may be powered by electricity or petrol that themselves can be hazardous. Workers should be properly equipped with appropriate safety wear: goggles, ear defenders, steel-capped boots, rubberised gloves. Practise safe lifting to minimise risk of back injuries. Planning of any job should include a risk assessment (see http://www.hse.gov.uk/pubns/indg163.pdf). If you need to work at height, use a platform or scaffolding system, not a stepladder. Electricity in the garden
1
Electricity is used for lighting, moving water features, irrigation systems and to power tools such as lawn mowers and hedge trimmers. Power cables must be installed by a qualified electrician and cables running underground must be appropriately housed. Where possible, to minimise risk use low-voltage or rechargeable equipment that is not connected to the mains when in use. If equipment is to be plugged into the mains, use an RCD (residual current device) that detects electrical faults and disconnects the supply. Use special waterproof outdoor fittings. See http://apps.rhs.org.uk/advicesearch/Profile.aspx?pid=442 Laying cable Cable should be laid at least 60cm (2ft) deep and in a place where digging is unlikely to take place, e.g. along a fence. (Under a path is theoretically safer, but the cable will be inaccessible should you need to replace it.) The cable should be armoured to prevent damage. Lay a warning tape 15cm (6in) above it. Construction of a slabbed patio Note: If a patio is to abut the house, it must be at least 15cm below the dampproof course Mark out the site with strings and pegs. Check that the corners are right angles with a builder’s square. Set the strings at the height of the finished paved area – they will act as a guide when laying the end pavers of each row. To achieve a suitable drop for run-off/drainage (a 2.5cm drop over 2m is recommended), lay a flat plank of wood across two pegs 2m apart. Between the second peg and the plank, insert a chock of wood 2.5m thick. Hammer in both pegs until they are level (check with a spirit level). Remove the chock, and the second peg will be 2.5cm lower than the first! Dig out the site. You need to allow for a lower layer of hardcore of 10cm topped by a 5cm layer of builder’s sand (topped by the slabs). Remove the roots of any weeds you come across. (You may wish to weedkiller the site at this stage and/or lay a permeable weed-suppressing membrane.) Tamp down the area with a whacker. Spread over the hardcore then tamp down. Spread the sand, then tamp down. Lay the first row of slabs directly on the sand (do not mortar them at this stage). Adjust the gaps between them as necessary (you can insert spacers between each so they are all even) and check that all are level. (If you need to stand on the sanded area, lay a plank on it to spread your weight.) When you are satisfied with the level, lift the first slab then put either five blobs (as on a die) on the sand that will grip the slab or (better) in four thin strips in a square shape (with a central cross if the slab is over 45cm across). When laying the second slab, check that it is level with the first with a spirit level. Continue laying the row, then tamp all down. Remove the spacers before the mortar sets. Two days later, fill the joins with stiff mortar, then brush the slabs down with a stiff brush. Decking Use decking where a lawn would be impractical or to terrace a gentle slope. Unlike paving, a deck has to be maintained and will need regular timber treatments. Timber is also slippery, even slimy, when wet. A deck is also far less durable than paving and cannot be viewed as a long-term solution
2
(unless made of very expensive materials). However, it is lightweight, cheap and quick to lay and easy to trim to shape. It’s essential that all the timbers are dry and that the deck is made during dry weather. When laying the decking boards, leave a 6mm gap between each to allow for seasonal swelling and shrinkage. Lay them loosely initially and allow them to dry out fully before screwing into position. Use corrosionresistant screws. If the deck attaches to the house, fix it in position to a ledger board. A ledger board is a horizontal timber attached to the house supported on spacers (to allow for ventilation). If you need to keep costs down, lay timbers diagonally. This allows you to make use of offcuts. Making the deck Dig a footing 10cm deep. Remove all traces of weeds (you can also weedkiller the area). Lay in a 10cm deep layer of hardcore, then tamp this down. Spread a weed-suppressing membrane over the top, holding this in place with a layer of shingle or grit. Construct a framework for the deck. Join the outer corners with angle irons. Within the framework, fix a series of parallel joists, 40cm apart. Lay the framework on the site (ideally, the joists should be supported on bricks or slabs – alternatively, hammer in a series of posts to either side of the joists). Check the level, then begin laying the decking timbers. Fences Fencing is usually used around the perimeter of a garden and sometimes within a garden to break up the space into smaller areas. Use solid fence panels to define the boundary and create privacy and security. Trellis fence panels can be used as screening within a garden both to divide it up and to provide a support for seasonal climbers such as clematis, honeysuckle (Lonicera) and roses (Rosa). Fence panels can be made of hardwood (oak, teak) or softwood (conifers, usually larch). Softwood panels are much cheaper than hardwood but less durable. Note: All timber should have been pressure-treated and will need to be treated annually to lengthen its life. To reduce the risk of rotting at the base, panels should not be in contact with the ground but raised slightly above it. Concrete fencing is a more durable alternative. Low fences (sometimes used in a front garden to mark a boundary) include picket fencing, post and rail, chain fencing, rope swags (good with a deck) or willow hoops. For screening within a garden, use bamboo (in an oriental garden), willow, wicker, plastic or concrete. To screen a vegetable plot (to reduce wind and keep out wildlife) use a utility screen – a tough, permeable windbreak fabric stretched between uprights.
3