What a Main Contractor Should Expect From a Cladding and Roofing Subcontractor

In practice that means an explicit list of what is needed at tender stage, a written survey before delivery, a sequence agreed with the trades that follow, and an inspection record your Assigned Certifier can use. This is how we work on site, and it is what you are entitled to ask of any cladding and roofing subcontractor in Ireland.

The information needed before pricing

A package priced from a two-line scope description will be re-priced later. To give a firm figure first time, we need:

• Drawings. GA plans, elevations and sections, plus any interface details for parapets, eaves, gutters, corners and door surrounds.
• The specification. Panel system and core thickness, target U-value, profile, external finish and RAL, liner, required reaction-to-fire classification and roof designation.
• Programme. Steel completion dates by zone, the date each elevation is released, and which trades follow behind.
• Access and logistics. Craneage, hardstanding, laydown area, working hours, and whether MEWPs or scaffold sit in your preliminaries.
• Scope boundaries. Who supplies secondary steel and liner, who owns roof penetrations, and who seals the M&E interfaces.

Two lines of the specification drive the rest. Under TGD L 2022, a building other than a dwelling is designed to area-weighted maximum elemental U-values of 0.21 W/m²K for walls, 0.20 W/m²K for a flat roof and 0.16 W/m²K for a pitched roof, with a higher worst-case point value permitted on individual elements[5]. On fire, TGD B places no restriction on roof coverings designated B_ROOF(t4) at any distance from the boundary, while the class required of the external wall depends on purpose group, height and distance to the relevant boundary[6]. If your insurer imposes LPS 1181 or FM conditions, tell us at tender stage. The certified thickness ranges are product specific[1].

Checking the steel before the first panel lands

Most programme losses on an envelope package are inherited, not created. Panels are made to tight tolerances and assume the frame is within tolerance too, so the survey happens before the first delivery, not on the first fixing day.

Panel and steelwork tolerances that matter before cladding starts

Item	Tolerance or dimension	Ref.
Panel cut to length	± 5 mm	[1]
Panel cover width	± 2 mm	[1]
Panel end squareness	± 3 mm	[1]
Steelwork between bearing planes of adjacent supports	± 5 mm	[1]
Support width assumed in the load/span tables	50 mm minimum	[1]
End bearing onto a purlin required by many composite panels	10 mm minimum	[4]
Purlin cleat position on the rafter	± 5 mm	[4]
Purlin cleat rotation from vertical	approx. 1°	[4]

MCRMA is explicit that ensuring the steelwork specification has been met is not the cladding subcontractor’s responsibility. It also notes that the main contract normally requires the subcontractor to check the secondary structure before starting and report any problem, and that one who starts regardless can be held liable for the rectification[4]. Our survey is therefore written, with photographs and a defects list, and issued before delivery. Panels have to butt up against one another to avoid cold spots where condensation can form[2], so squareness is measured, not assumed.

M&E is treated the same way. Penetrations are set out before panels are fixed, and where site cutting is unavoidable a powered reciprocating or circular saw is used, never an abrasive cutting wheel, with swarf removed immediately and touch-up lacquer applied[2].

Site set-up, sequence and reporting

Panels are stored on bearers at approximately 2 m centres, laid to a slight fall for drainage, and lifted from the pack rather than dragged[2]. Work at height is governed by the Safety, Health and Welfare at Work (Construction) Regulations 2013[8], and the HSA Code of Practice for Safety in Roofwork states that the roof assembly should be non-fragile Class C as a minimum to ACR[M]001[7].

Roof panels are laid ridge to eaves, starting with the female edge at the gable away from the prevailing wind, side laps stitched at the manufacturer’s recommended centres, typically 450 mm, with the seal on the weather side of the fasteners, three runs of sealant at end laps and a single run at side laps, generally 6 mm × 5 mm Class A butyl[2]. Aluminium fabrications follow their own regime: ridge and hip flashings at typically 400 mm centres maximum, verges at typically 500 mm maximum[3]. Panel length is a programme lever. Standard lengths run from 1.8 m to 14.5 m and non-standard lengths to 29.2 m[1], so fewer end laps mean fewer sealed joints and fewer inspection points.

What you should receive each week is the same short report: square metres planned against square metres installed by elevation or roof bay, operatives on site, deliveries booked, what is blocking us, a two-week look-ahead and a dated photo record. If a subcontractor cannot produce that on a Friday, the programme is being managed from memory.

Quality checks and handover

Our completion check follows the MCRMA finishing sequence: every fastener correctly installed and tightened without distorting the panels, damage treated, surfaces left clean[2]. Aluminium copings and flashings are checked for one fixed point per length with the remaining fixings floating in slotted holes, since an allowance of the order of ± 1 mm per metre of movement must stay available[3].

The handover pack is assembled as the work proceeds. It holds:

• the CE marking and declaration of performance for the system, which is CE marked to BS EN 14509:2013[1],
• the warranty registration, which for the QuadCore range covers 25 years thermal, fire, structural and environmental performance and up to 40 years on the coating[1],
• the fixing schedule and the as-built survey,
• our ancillary certificate.

That last item matters under BCAR. The Code of Practice notes that a project normally has certifiers beyond the Assigned Certifier, subcontractors, suppliers and manufacturers among them, and that the builder must ensure the coordination and provision of all test certificates and confirmations to the satisfaction of the Assigned Certifier[9]. A subcontractor who cannot produce that paperwork on request is a certification risk, not just a snagging one.

One figure is worth recording at handover. TGD L treats 5 m³/(h·m²) at 50 Pa as a reasonable upper limit for air permeability in buildings other than dwellings, tested on completion[5], while 3 m³/hr/m² at 50 Pa or less is stated as achievable using Kingspan insulated roof and wall panels[1].

In short

The subcontractor you want on a tight envelope package asks awkward questions at tender stage, surveys the steel before delivery, reports the same numbers every week, and arrives at handover with the certificates already collated. Clad-Primeco is an experienced installer of Kingspan insulated panel systems and architectural façade panels, working for main contractors, developers and the public sector in Dublin and nationwide.

Frequently asked questions

Sources

1. Kingspan, QuadCore KS1000 RW Roof Panel, product data sheet, Insulated Panels UK & IrelandAccessed 14 September 2026
2. MCRMA GD17, A guide to site installation of insulated roof panels (2015, updated 2019)Accessed 14 September 2026
3. MCRMA GD26, Aluminium fabrications: a guide to good practice (2020)Accessed 14 September 2026
4. MCRMA GD27, Installed tolerances: best practice design guide (2016, updated 2020)Accessed 14 September 2026
5. Department of Housing, Local Government and Heritage, Technical Guidance Document L, Conservation of Fuel and Energy, Buildings other than Dwellings (2022)Accessed 14 September 2026
6. Department of Housing, Local Government and Heritage, Technical Guidance Document B 2024, Fire Safety, Volume 1: Buildings other than Dwelling Houses (2026 Edition)Accessed 14 September 2026
7. Health and Safety Authority, Code of Practice for Safety in RoofworkAccessed 14 September 2026
8. S.I. No. 291 of 2013, Safety, Health and Welfare at Work (Construction) Regulations 2013Accessed 14 September 2026
9. Code of Practice for Inspecting and Certifying Buildings and Works, Building Control Regulations 1997 to 2015 (September 2016)Accessed 14 September 2026