Under floor membranes

Polyolefin membranes should be placed beneath all slab-on-the-ground foundations, irrespective of site and ground conditions.

The membranes should have a thickness of not less than 0.25mm and should be placed beneath the slab and beam thickenings so that the bottom surface in entirely laid.

Where justified by appropriate geotechnical conditions, the membrane as in the case of slab-on-the-ground features, may be terminated at the face or edge of the internal beam.

Lapping of membranes at joints should not be less than 200mm.

Penetrations by pipes, plumbing fittings or punctures should be taped with a pressure sensitive adhesive tape.

In the case of floor tabs, the membranes should be turned up around the perimeter of the floor slab by at least the thickness of the slab.

Compaction

The maximum height of fill beneath floor slabs and slab-on-the ground foundations measured at the lowest point should not exceed 400mm unless certified by the engineer.

Fill should be moistened prior to compaction so that a handful squeezed in the hand is firm but does not show signs of moisture. Fill should be placed in uncompacted layers not exceeding 100mm in respect of hand compaction or 150mm in respect of mechanical compaction.

Each uncompacted layer should be well compacted before additional fill material is added.

Compaction should be such that in excess of 3 blows of a dynamic cone penetometer are required to penetrate 100mm of the fill, provided that fills do not comprise more than 10% gravel size less than 10mm and contain no isolated boulders.

Dynamic (drop weight) cone penetrometer

This is an instrument used to measure the in situ shear resistance of soil comprising a drop weight of approximately 10 kg which falls through a height of 460mm and drives a cone having a maximum diameter of 20 mm (cone angle of 60 degrees) into the material used.

Our customers influence our performance objectives

We seek to satisfy customers through developing a few typical performance objectives.

When customers value our cost-effective pricing the operation will place emphasis on its cost performance.  If a customer insists on error-free services the operation will concentrate on its quality performance.  When a customer emphasizes fast delivery we will make speed important within the operation important while an emphasis on reliability will make dependability important.  When customers expect an innovative service, the operation must provide a high degree of flexibility in order to get its innovations to its customers before its rivals.  If a wide range of services are demanded by customers, the operation will need to be flexible enough to provide the necessary variety without excessive cost.

How well we meet your requirements is determined by how well our operation excels at these performance objectives which will subsequently influence the competitive factors.

Requirements of single storey masonry construction

·         The height of the wall from the floor level to the top of the external gable does not exceed 5.0 m

·         The span of roof trusses/rafters between supporting walls do not exceed 8.0m and for a concrete roof slab the restriction is at 7.0m

·         The dead load of the roof covering in a roof other than a concrete slab does not exceed 80 kg per square metre

·         Concrete roof slabs should not be thicker than 255mm if of solid construction or the equivalent mass if of voided construction

·         The height of the foundation walls should not exceed 1.5m

·         The height of the fill beneath the slabs should not exceed 1.0m