Services without compromise
The electrician wants to chase the wall, the plumber wants a straight drop, and the builder does not want to weaken a panel on site. Self builders worry about holes in a new shell, while turnkey clients expect a clean finish with no rework. When service routes are planned and sealed, the envelope stays strong and airtight. UltraSIPS aligns service zones with the layout drawings so penetrations are treated as details, not last-minute cuts.
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.
Comparison
Coordination priorities
Decide these before the shell is closed.
Electrical
- Chase locations and depth
- Switch and socket positions
- Avoid splines and load paths
Plumbing
- Vertical drops planned
- Avoid large bore cuts through structural zones
- Confirm wet room locations early
HVAC
- Duct routes and plant location
- Supply and extract balance
- Service void requirements
Envelope sealing
- Penetration gaskets and tapes
- Airtightness sequence
- Testing plan
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.
Comparison
Cavity vs chase
Choose the route that protects the structure.
Service cavity
- No cutting into panel core
- Flexible for late changes
- Adds depth to internal lining
Factory chases
- Clean and efficient
- Best for repeatable layouts
- Needs early coordination
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
Comparison
Ventilation strategies
Match the strategy to the shell and client expectations.
MVHR
- Best for airtight SIP shells
- Recovers heat while ventilating
- Needs planned duct routes
MEV
- Simpler than MVHR
- Works with good background ventilation
- Lower heat recovery
Passive vents
- Lowest cost
- Harder to control in winter
- Not ideal for very airtight shells
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.
Comparison
Testing the build
Testing proves performance and catches leaks early.
Blower door test
- Measures air leakage at 50 Pa
- Finds leaks before finishes
- Required for compliance
Duct pressure test
- Checks HVAC leakage
- Improves system efficiency
- Avoids future call-backs
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.