GUIDES

Laying Paving Slabs

Planning

Decide upon your paving and the number of sizes you require commensurate with your preferred laying pattern. Draw a scale plan on graph paper, outlining house, garden and the intended paved area and where possible adjust any perimeter edges to suit paving sizes to avoid unnecessary cutting. In differing colours per size draw in each slab to act as an ordering and laying guide. Arrange for all your paving requirements to be delivered before the onset of the project and stack nearby on a dry base.

Site Preparation

All paving should be laid on a firm, level and well-drained base to ensure long term service and stability - getting the ground work right is essential. Vegetation and top soil should be removed to an approximate depth of 200mm across the area to be paved. Mark out this area with pegs or retaining boards and adjust their height to the required finished surface levels, ensuring that you allow a fall of 1:60 away from any buildings and walls for surface drainage. Also make sure that the finished paving surface level is at least 150mm (two brick courses) below the level of any damp proof course.

After excavation, rake level to ensure an even depth and compact the whole area using a garden roller or tamper. Then lay at least a 75mm deep sub-base of crushed stone or hardcore and compact well (your local stockist will be able to advise you on a suitable material). If there are voids after compacting the sub-base, rake in sand and compact again. Spread a layer of sharp sand across the sub-base, to a compacted depth of 35mm.

The alternative is to have a wet mix of 4 parts sharp sand with one part cement, mixed to a consistency that is moist but not overly wet. Wet mortar can be messy. Light coloured flagstones, and those formed from granite are often prone to discolouration when laid onto mortars made using strongly-coloured sand, such as the orangey sands common in SE England. For these flagstones, we recommend that the laying mortar should be prepared using 6 parts neutral coloured sand (often sold as "Silver Sand") and 1 part white cement. This will minimise any risk of discolouration whilst ensuring your new paving is properly bedded and fully supported.

Laying   back to top

It is always preferable to start with full flags laid adjacent to a fixed point such as the house or boundary wall and to work towards an edge which may be adjustable. Alternatively start from a corner on the longest straight edge. If you are laying more than one size of paving, particularly if in a random pattern, or if you are laying a circle or other feature, it is recommended that you dry lay the flags first to check the fit and make sure you are happy with the pattern. For greatest stability the paving should be laid on a full mortar bed, using a wet mortar mix of 5 parts building sand to 1 part cement. This is essential if you are using one of the Purestone natural stone paving products.

We advise that you take the paving from a number of open packs at once, even if you are just using one size, to ensure a consistent appearance to the finished patio.

Tap each paving stone down to the required level, keeping a piece of softwood between the hammer / mallet and flag (alternatively use a rubber mallet). Continually check levels and falls during the laying process across the top surface profile of a number of flags at a time. It is important to ensure correct spacing between the flags, although please note that for random patterns the joint widths can vary.

Pointing   back to top

Pointing can be completed as laying work progresses by "buttering" the sides of previously laid flags with mortar, and then smoothing or raking out the joints later when the mortar has started to set. Alternatively, the gaps may be pointed once laying is complete and the mortar is set using a semi-dry mortar mix of 6 parts building sand to 1 part cement. Take care not to stain the paving surface; any spillage should be removed immediately using a damp cloth or sponge. Do not attempt to brush the pointing mix across the surfaces of the flags as any cement left on the flag will result in unsightly staining.

A full mortar joint is recommended to ensure maximum surface water drainage and all joints should be smoothed or raked out using a suitable rounded piece of wood, a piece of pipe or a specialist pointing tool.

Manufactured reconstituted flag paving is suitable for domestic garden use only. It is not suitable for driveways or heavy traffic.

For driveways any of Domestic Block Paving, Purestone Paving or Stone Setts (i.e. Sandstone or Granite) may be used providing they are laid on a suitable sub base.

Romex Grouting   back to top

Romex Easy Pointing / Grouting Mortar
The easiest pavement fixing mortar. Suitable for frost and de-icing salt resistant, weed free, abrasion resistant, environmentally friendly, quick, cost effective and permanent joint fixing of almost all natural and concrete paving stones, slabs and clinker surfaces.

Laying Setts and Cobbles   back to top

The area to be laid should be excavated to a depth of 200mm, removing any topsoil and vegetation and ensuring where applicable that falls slope away from buildings and walls with at least a 1:60 gradient. You should make sure that the finished surface level is at least 150mm below the damp proof course. Lay a minimum depth of 75mm compacted stone to cover the excavated area. Then lay a minimum depth of 100mm wet concrete bed foundation using 4 parts coarse aggregate to 2 parts building sand to 1 part cement.

Lay the setts on a 40mm compacted thickness of semi-dry cement mix (3 parts sand to 1 part cement) with a nominal joint width of 15-20mm. Bed the sets down with a pavior's maul and then fully compact (for large areas the hire of a plate vibrator is recommended). In dry weather and when the setts are dry fill the joints and pack firmly as the work proceeds with a semi-dry mix of 3 parts sand to 1 part cement, ensuring no pointing mix remains on the surface of the setts.

If no vehicular traffic is expected, the setts may alternatively be bedded on mortar laid onto existing firm and stable concrete surfaces or similar.

Sealing   back to top

Pave Shield
Pave Shield will enhance, seal and protect natural stone, terracotta, concrete block paving and slabs. It provides an effective barrier against ingress of dirt, oil, food or drink spillage to simplify maintenance and cleaning. The original colours of stone or concrete products remain virtually unchanged. Darker tones may be improved or enriched. Sealing also helps to provide resistance against formulation of efflorescence on to hard landscaping surfaces.

• Water based coating - making sealing simple and safe.
• Resists penetration from oil, grease, food and dirt.
• Long coating life - up to 4/5 years under normal trafficconditions.
• Protects your investment.
• Virtually invisible.
• Makes cleaning effortless and prevents surface dusting.
• Stabilises jointing sand.

Geofix Stone Protector
Based on an advanced Fluoro-Resin formula, Geo-Fix Stone Protector has been specially developed to provide highly effective long lasting protection on Natural Stone and Mineral Surfaces. Importantly, particularly when using on expensive high quality Natural Stone, Geo-Fix Stone Protector is totally invisible and will not change the colour or appearence of the stone.

Building Walls   back to top

Strip topsoil, dig to firm ground and lay level concrete foundations. As a rule of thumb a foundation should be dug approximately one third of the total wall/feature height (minimum depth 100mm) and foundation width should be three times the width of the wall. A recommended foundation mix would be 4 parts coarse aggregate to 2 parts building sand to 1 part cement. Stretch a building line between the ends and build one course at a time, checking for accuracy vertically, diagonally and horizontally using a spirit level. Using a trowel, spread mortar (4 parts building sand to 1 part cement) evenly over the foundations and then over the blocks in each course as you lay them; the mortar should just exude from between the joints and any surplus is taken off with the trowel. Don't forget to fill the vertical joints as you go by applying mortar to one end of the block before positioning it adjacent to the previously laid block. The blocks should be laid in a stretcher bond using half blocks at the end of each alternate course.

Using a pointing trowel, smooth and finish the mortar joints. Top with the required coping.

Please remember for retaining walls higher than 600mm and any wall built over one metre high, professional advice should be sought prior to construction.

If you are building a raised planter, barbecue or similar small garden feature on an existing concrete base or well laid patio, foundations may not be required.

Installing Edging   back to top

Whilst our edging range can be laid directly into the ground, for stability a more permanent method of fixing is recommended. This may be achieved by digging out a small foundation trench to the required length, approximately 100mm deep and 150mm wide. Fill and level with a foundation mix of 4 parts coarse aggregate to 2 parts building sand to 1 part cement.

Once the foundations have cured, bed the edging by gently tapping the top edge with a rubber mallet into a mortar bed of 4 parts building sand to 1 part cement, ensuring each unit is aligned and level. Back fill the reverse face of the edging with the same mortar mix "haunched" with a 45 degree wedge of mortar to a height that will be concealed by the finished surface.

Laying Stepping Stones   back to top

1. Evenly space the stepping stones across the lawn or border.
2. Using the stepping stone as a template, cut away the surrounding turf or soil to a depth of approximately 75mm.
3. Infill with sharp sand to a depth of 35-40mm or use a weak semi dry mix of 5 parts sand and 1 part cement.
4. Place stepping stone and tap down gently with a rubber mallet so that it sits just below the level of the lawn.

Using Decorative Aggregates   back to top

Clear the required area, removing all loose material and vegetation (use weedkiller if necessary on any deep-rooted weeds). Lay a semi permeable membrane over the whole area, with a minimum of 50mm overlap between sheets. Lay the decorative aggregate to the required depth (40mm is sufficient for most applications but check the packaging for any instructions specific to your product). Rake to achieve the required surface level. Although decorative aggregates can be laid directly onto soil it is recommended to use a membrane to minimise weed growth.

To help you obtain the up most satisfaction and long service from our product range we are happy to make you aware of the following:

Colours   back to top

The colours depicted on this site are as accurate as modern photography and printing processes allow. Tonal variations are evident in all manufactured and natural stone products, we therefore recommend that colours are judged from actual materials. This is of significant importance when selecting a natural stone product which, by its very nature, each component will exhibit considerable deviations. It is important to view a range of samples at a stockist to acknowledge the authentic diversity in colours, texture and markings.

Manufactured products are designed to simulate natural stone and naturally occurring aggregates are utilised, therefore variation between batches can occur. To produce a natural overall appearance when using two or more packs of product we suggest that individual products are drawn from each pack and mixed on site at the onset of the project.

Reconstructed stone products will weather in a similar way to natural stone, therefore the effect of the elements and site conditions may cause some colour change dependent on the degree of exposure. After laying, some natural stone products may exhibit a brown colouration when oxidation of any iron content occurs.

Maintenance / Cleaning   back to top

Regular maintenance is required to keep the overall appearance of the product in pristine condition. We recommend thoroughly washing paved areas with warm soapy water and brushing off with a stiff broom three or four times a year.

We cannot be held responsible for the possible effects or damage caused by the contamination or application of some chemically based products which come into contact with a concrete surface e.g. some weed killers and acid or alkali based cleaners.

Common salt should not be used to de-ice wet cast paving. To prevent possible surface damage always use a proprietary brand of de-icing product expressly formulated for use on concrete.

Sweeping
Regular sweeping with a broom will remove most of the usual litter and garden debris that finds its way onto all pavements. Occasionally, it can be beneficial to hose down the paving, adding a dash of basic detergent if required to help remove any surface stains. For sensitive paving such as limestone´s, many cleaning specialists prefer to use a mild baby shampoo in place of standard detergent as they believe this runs less risk of damaging the natural colouring of the stone. Scrubbing with soapy water and a stiff brush will help shift any awkward stains, but don't be tempted to use anything overly abrasive, such as steel wool or wire brushes as these can leave marks on the surface of your paving.

Power Washers
High pressure washers are not recommended for use on manufactured paving. Power washers can help clean heavily soiled paving but they should be used sparingly and with great care. They can damage the surface of the stone and/or the jointing if not handled correctly. If a power washer is to be used, we would strongly recommend the use of a ´rotary cleaning head´ rather than the more usual ´lance´ as these are less damaging to the paving while still being very effective against dirt. When power washing is used, it should be limited to one, and a maximum of two sessions per year. Patios and driveways that are power washed on a regular weekly or fortnightly basis tend to develop structural problems such as failed jointing, settlement and excessive surface wear of the paving.

Drainage   back to top

When laying a patio or path close to a house or dwelling it is essential that the finished paving surface is at least 150mm below damp course level and should slope away from the building. (A fall of 1:60 is generally sufficient). All paved areas should be gently sloping to allow excess water to be directed away and should always be laid on well drained ground. Any base preparation should also allow for drainage. Poor drainage may result in water retention and may affect the weathering characteristics of the materials.

General Information   back to top

Awkward Stains
For heavy staining, such as oil drips, autumnal fruits, bird droppings, etc., if basic cleaning using hot, soapy water does not work, we would recommend that you seek specialist advice from a surface cleaning professional. Many of the ´patio cleaners´ sold in DIY store or Builders Merchants are based on strong acids that can irreparably damage certain types of stone or adversely affect the natural colouring. Always test any cleaning product on a surplus flagstone or sett or in a discreet corner before applying it to the paving.

Efflorescence
Efflorescence is a problem more commonly associated with concrete paving, as the characteristic white powdery deposit originates in the calcium carbonate of the concrete, but it can also affect natural stone paving when it is laid on mortar or concrete. While the appearance of efflorescence can detract from the looks of a new pavement, it is important to understand that, no matter how bad it may seem, it is temporary, that it will pass with time, and that it is not actually damaging the stone. There are efflorescence removers that can be used to wash away the worst of any deposit, but they are removers, not cures, and it is quite likely that a new deposit will appear within a few days, although it may not be as heavy as the original deposit. Simple washing with warm soapy water will usually achieve the same, and at a much lower cost!

LSD Sizing/Dimension Policy
All dimensions given are nominal and subject to manufacturing tolerances. The quoted dimensions of our paving ranges are those normally attained when the slabs are arranged correctly spaced.

Product Colour Variation
Tonal and colour variations are evident in all Strata products and whilst the colours reproduced in this brochure are as accurate as photographic and printing processes allow, it is essential that your choice is made from actual materials at your local stockist. This is particularly important when choosing Natural Stone products where considerable variation occurs.

When using several packs, products from all the packs should be blended throughout the project to produce an acceptable overall natural appearance.

Laying Patterns   back to top

600 Series Laying Pattern for 15.3sqm Packs
Here is a pattern for the 15.3sqm patio packs.