A structural metal tray lining system designed to replace timber rafters.
Each tray side-laps its neighbour and are fixed directly to the purlins, running from eaves to ridge.
This system creates a traditional tiled or slated roof without the congestion or fire risk of a timber construction.
It does not affect the practice of tiling or slating, since the installation of underlay, tiling battens and tiles remains identical and the completed roof displays no visible evidence of its use.
Standard product features
- Sheet cover width: 500 mm.
- Thickness: 0.75 mm and 1.0 mm.
- Weight: 8.83 kg/m² and 11.78 kg/m².
Roof loadings and spans:
The primary function of Tactray 90 is to support the dead and live loads associated with the roof.
Spans up to 4800 mm are possible, depending on loading and material thickness.
Refer to the load and span tables in the technical literature.
The trays are secured through the pan to the steel purlins using washered fixings.
Softwood counterbattens are fixed to the tray upstands using self-drilling fixings which must penetrate both thicknesses of steel in order to ensure adequate pull-out strength.
Factory fitted 50 x 50 mm timber counterbattens can be supplied if required.
The maximum sheet length with counterbattens is 7 metres.
Sheets with counterbattens above this length are subject to confirmation and will attract an additional charge.
When correctly laid and sealed, Tactray 90 meets the requirements of BS 5250: 1989 and approved Document F2.
Providing the internal humidity does not exceed the limits given, there will be no significant accumulation of condensation on the internal surface.
The maximum internal relative humidity is 86% for an internal temperature of 20°C and an external temperature of 5°C.
When correctly installed using TacMat quilt, and with the insulation provided by the air spaces and slates or tiles, the Tactray 90 should be at ambient room temperature.
At this temperature, thermal expansion does not present a problem.
Light and optical performance:
The optional brilliant white inner face has a reflectivity index of 79%.
A perforated version is offered for enhanced acoustic performance.
This is not covered by the BBA certification.
Under normal atmospheric conditions, the steel and galvanized finish remains unaffected.
Tactray 90 is impervious to insects, birds, vermin, fungal and biological attack.
If localised conditions are such that Tactray 90 may be exposed to specific liquid, gas or solid chemical pollutants, Haironville TAC Limited should be consulted.
When correctly installed by an approved contractor in accordance with the manufacturer's instructions, Tactray 90 would be expected to have a serviceable life in excess of 60 years.
The galvanized coating would typically protect the steel substrate for at least 15 years and when the polyester finish is specified, the expected period of protection offered by the coating system would be over 25 years.
This anticipated performance would be reduced where the product is subject to high humidity levels or where exposure to chemical contaminants or physical damage occurs.
Tactray 90 incorporates a factory fitted side flange vapour control seal along the entire length of the tray.
This significantly reduces the risk of interstitial condensation within the insulation zone.
Allowing a maximum internal relative humidity of 86% for an internal temperature of 20°C and an external temperature of 5°C.
Where a softwood timber treated with preservative is used, the preservative manufacturer should be consulted regarding potential electrolytic corrosion of the galvanized tray or fasteners.
The allowable maximum moisture content of the timber is 20%.
Run-off water from lead or copper flashings should also be prevented from coming into contact with the galvanized surface of Tactray 90.
Tactray 90 provides a short-term weatherproof seal against the elements, should the slates or tiles become dislodged.
It also prevents access by intruders where high value goods are stored.
Its continued integrity also offers enhanced security for police stations and prisons, etc.
No maintenance is required apart from occasional cleaning of the internal painted surface where required.
Where a change of colour is required, an approved proprietary paint system should be used.
Designed for ease of installation, Tactray 90 is easily cut on site and is fixed by contractors recommended by the manufacturer.
A maximum vapour resistivity of 0.25 mN/s/g is recommended, and is laid over the insulation and counterbattens.
The sheets are roll-formed from galvanized steel with a thickness of coating to Z275 to BS EN 10147: 1992. The standard finish is galvanized.
The sheets are also available with the internal surface coated with a brilliant white, 25 micron polyester paint applied over the primer and galvanizing.
Other colours may be possible according to quantity.
- TacMat 140 Plus: 140 mm thickness. Lambda: 0.037 W/m²K. U-value: 0.25 W/m²K.
- Mineral wool: 165 mm thickness. Lambda: 0.037 W/m²K. U-value: 0.20 W/m²K.
- Mineral wool: 190 mm thickness. Lambda: 0.037 W/m²K. U-value: 0.18 W/m²K.
- TacMat insulation is available from Haironville TAC Limited.
- The insulation is laid in the pans.
- Self-adhesive insulation hangers, or 'stick pins', are available and recommended for steep pitches to prevent 'slumping' of the insulation. They are fixed at 3m centres.
A complete range of flashings is available in white or galvanized finish.
All flashings are made to order from drawings submitted by the contractor to suit the dimensions of each project.
Certification and attestation:
British Board of Agrément:
Tactray 90 has been awarded British Board of Agrément Certificate No. 95/3192.
- Coated steel sheeting, tested to BS 476-5: Ignitability test was graded 'P' - not easily ignited.
- Surface spread of flame test to BS 476-7: 1971: Gave an index of performance within the requirements of a Class O surface as defined by the current Building regulations and the Building Standards (Scotland) Regulations.
- The material used in the manufacture of Tactray 90 has a Class 1 surface spread of flame to BS 476-4 and meets the Fire Officers Committee (FOC) rules for use in Class 2 buildings.
Air leakage control:
In independent tests carried out by the BBA, Tactray 90 achieved a maximum air leakage rate of 4.1m³/HR/m² at a pressure difference of 50 pascals, considerably better than the minimum air leakage standards required by the Building Regulations.