Fusion Provida

Gainsford Drive Roof Report
& Recommendations

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Following our inspection of the roof at Gainsford Drive, Halesowen, we are pleased to provide the following report.

It should be noted that only a limited inspection was possible due to inclement weather conditions and lying snow to much of the surface on the date of our visit, 1 February 2009.

Findings

The existing asbestos roof is generally in a fair and serviceable condition, though it was noted that there have been a number of prior and, poor repair attempts using flash band and bitumen coating on cracked and damaged roof sheets, skylights and flues.

The asbestos roof sheets have a covering of moss and algae which in some areas has engrained itself into the asbestos roof sheets and has started to spall, releasing asbestos fibres in isolated areas.

The boundary and valley gutters have a large build up of live vegetable matter and debris restricting the gutter’s capacity to cope with heavy rainfall, leading to the water ingress problems.

Most of the roof fixings have retained their caps but it was noted that some of the fixings and caps are becoming loose, with some corrosion evident.

Recommendations & Options

The following options should be considered in conjunction with the lease arrangements on the property and the landlord’s permission should be sought prior to commencement of any works.

Option 1 – Skylight Replacement & Repair

All of the skylights appear to be at the end of their useful life, with delamination widely evident and poor quality repairs having been previously undertaken.

Remedy:

Clean back all of the previous old repairs, supply and fix up to 6 no GRP, DR repair sheets of a matching profile over any non-repairable roof sheets, smaller areas of repair should be cleaned back to a suitable substrate, a primer sealer applied with a reinforcing membrane over the damaged area allow drying time then apply a fully weather proof coating system to all of the areas of repair in full accordance with manufacturer’s specifications and recommendations.

Any loose or leaking roof fixings should be sealed or replaced using an elastomeric sealant.

Any loose or slipped eve filler blocks should be reinstalled and mechanically fixed and the same with any ridge or barge flashings.

Carry out a thorough industrial clean of all the boundary and valley gutters, remove all debris lower to ground and remove from site and leave fully free flowing, blocked down pipes to be rodded down to ground level, on any internal leaking gutter joints clean back gutter joints apply a elastomeric sealant directly in the joint thereafter supply and fix a reinforcing membrane over the joint apply a primer sealer allow drying time then supply and fix Britannia Aqua Shield fully weatherproof coating system to the full girth of all the gutter joints and 100 mm either side of the joint.

Remove all of the skylights, lower to ground and remove from site, thereafter supply and fix new GRP class 3 8oz skylights of a matching profile complete with all new fixings.

Budget cost including scaffolding and health & safety requirements: £9500 + VAT

Option 2 - Clean & Re-Coat

This option includes everything contained in option 1 in addition to:

Soft wash and fungicidal clean of the asbestos roof in order to obtain a suitable sound substrate, thereafter application of a primer sealer coat followed by a fully weatherproof asbestos roof coating system supplied and applied in full accordance with the manufacturer’s recommendations and specifications. This option comes with a 10 year manufacturer’s guarantee.

Budget Cost: £19,500 + VAT – assuming that H& S equipment and scaffolding is in place from option 1 above.

Option 3 – Overclad Existing Roof

New Metal Profile Sheet Overclad System

Fix a new ash grid galvanized metal external purlin system, mechanically fixed to the existing purlins, with a 190 mm Insulation quilt laid into the void to aid the U value of the building.

Remove old delaminated skylights and replace with new GRP 6oz skylights into the existing roof, install new galvanized plastisol coated steel 0.7 gauge roof sheets to the colour of your choice over the existing roof, including new GRP 8oz class 3 outer skylights complete with new fixings, caps and washers. All laps to be sealed using butyl mastic complete with all new barge flashings, ridge capping & closures.

New galvanized detail flashings to be installed in conjunction with new deck tights around the flues where required. The budget costs include for all new inner and outer skylights and the specification of Corus or Kingspan branded roof sheets.

All works to be carried out in full accordance with the manufacturers recommendations and specifications.

Budget Costs: £40,600 + VAT 20 year manufacturers guarantee

Conclusions

Each of the options has it’s own advantages depending ultimately on the length of time you plan on staying in the building.

Option 1 – The replacement of the skylights is considered essential, as is cleaning and repair of the gutters and rainwater goods, since this is the usual cause of many water ingress problems.

Individual repair of damaged roof sheets is possible, but given the age and general condition of the roof, such repairs can only be considered temporary and it is likely that on-going maintenance and repair will be required.

The cost of health and safety equipment, scaffolding etc will have to be borne with each subsequent repair.

Option 2 – Cleaning and coating the roof, in addition to replacing the roof lights, cleaning and repairing the rainwater goods is a cost-effective option if you anticiapte a short-term tenancy of the building, assuming that the landlord is in agreement.

Whilst coating systems carry a ten year guarantee, it is unlikely that the system will last much longer than this and further attention might be required in the interim.

Option 3 – If intending to remain in the building for ten years or more, then option 3 provides certain advantages.

The level of insulation provided with this option will undoubtedly result in fuel cost savings and the addition of new roof lights will bring more natural light into the premises than is currently afforded.

The landlord benefits from a 20 year guarantee on the roof and may be open to some negotiation of terms on the new lease.