Lesson 8: Integrating Mechanical Systems

Services without compromise

Services are where good SIP shells get compromised. When routes are planned and sealed, the envelope stays strong and airtight. UltraSIPS aligns service zones with layout drawings so penetrations are treated as details, not last-minute cuts.

Unplanned services weaken panels and break airtightness, so coordination matters early.

The golden rule

Treat service runs like structure. If you cut without a plan, you lose both strength and airtightness.

Working with other trades

MEP coordination is a team sport. Builders, electricians, plumbers, and HVAC designers must agree on routes before panels arrive.

Service cavities vs chases

There are two main strategies:

• Service cavity: add a battened void inside the panel.
• Pre-planned chases: factory-routed channels for wiring.

Label your chase locations

Clearly label chase zones on the drawings and the panels. This prevents random cutting and keeps trades aligned.

Electrical in SIPs

Electrical runs should avoid splines and concentrated loads. Where possible, keep wiring in service zones or cavities.

Plumbing chases

Large diameter pipes should not cut through structural cores. Use planned drops and service voids.

Roof applications and shielded cables

Roof panels often carry lighting and PV wiring. Use shielded cable or conduit and keep routes clear of structural joints.

Penetrating the envelope

Every penetration must be sealed. Use grommets, tapes, and sealants compatible with the panel skin and internal lining.

HVAC analysis and design

Airtight SIP shells need a ventilation strategy that matches the build. MVHR is common in the UK, but even simpler systems require planned supply and extract routes.

Humidity control

Tight buildings trap moisture if ventilation is undersized. Balance extract in kitchens and bathrooms, and avoid excessive indoor humidity during first heating.

Ventilation strategies

Conditioned crawlspaces

If you use a crawlspace, treat it as part of the envelope. Insulate and seal it properly to avoid moisture and cold floors.

Testing the envelope

Airtightness is measured, not assumed. Plan for blower door testing and duct leakage checks.

Plan for sealing

Write a sealing plan for every penetration and joint. Decide who seals what, and when.

MEP checklist

• Plan service zones early.
• Use cavities or factory chases.
• Label chase locations.
• Seal every penetration.
• Coordinate MEP with layout drawings.
• Plan HVAC and humidity control.
• Schedule airtightness testing.