My Timber Frame Is Raised—Now What? Enclosure, SIPs, and Early Decisions

Enclosing a Timber Frame: Panels, SIPs, and Critical Early Decisions

Once your timber frame is raised, the enclosure process begins. This phase moves quickly—but it requires early coordination and clear decisions. There are several wall and roof system options, each with tradeoffs. We’ll cover the pros and cons of each system in detail in a future post.

For now, our general recommendation for most projects is panelized wall systems or SIPs (Structural Insulated Panels).

SIPs are a common choice for timber frame homes because they allow for rapid enclosure, excellent thermal performance, and long-term protection of the frame.

A solid primer on SIP construction can be found here:
What Are SIPs? – Premier Building Systems
https://sips.premierbuildingsystems.com/blog/what-are-sips-the-basics-of-structural-insulated-panels

Why Panels or SIPs?

The advantage of panels is speed and contiguous exterior layer. Faster, moisture resistant enclosure means:

  • Reduced weather exposure for the timber frame

  • Lower risk of staining, checking, or moisture intrusion

  • Earlier transition to interior work

Panels also provide structural shear, which gives you more flexibility in interior finishes and sheathing choices.

Early Coordination: Electrical, Plumbing, and Services

Before panels are ordered, several decisions must already be made.

Key questions include:

  • Will drywall (gypsum) or board sheathing be installed before panels?

  • Where will electrical and plumbing runs be located?

  • How will service paths be routed?

Chases and Service Planning

In panelized systems, electrical and plumbing can be routed through prefabricated chases built into the panels. These must be planned in advance.

This requires:

  • A developed floor plan

  • Known outlet, switch, fixture, and plumbing locations

  • Defined routing paths

Late changes are costly once panels are fabricated.

Birdcages (Service Cavities)

One common solution is a service cavity, often referred to as a birdcage. This is typically a 2×4 or similar framed gap installed to the interior side of the panels.

Benefits:

  • Keeps wiring and plumbing out of the panels

  • Protects drywall installation from the elements

  • Flexibility in routing/design changes.

Drywall installation occurs after services are ran.

We recommend working directly with your panel manufacturer to coordinate:

Sheathing Options: Boarding vs. Gypsum

With a timber frame, think of:

  • Timbers as the skeleton

  • Sheathing as the connective tissue

Because panels provide structural shear, your sheathing choice is largely driven by aesthetics and sequencing, not structure.

Common Sheathing Options

  • Board Sheathing

    • Traditional appearance

    • Often used on ceilings and roofs

    • Offers limited short-term weather resistance during construction

  • Gypsum (Drywall)

    • Clean, contemporary appearance

    • Common on walls

    • No weather resistance—panels must follow immediately

OSB is generally avoided as an exposed interior sheathing due to appearance.

A common approach we see:

  • Boarded ceilings / roof planes

  • Gypsum walls

Gypsum throughout can create a contemporary look; full boarding leans traditional.

Weather Barrier and Panel Installation

After sheathing is installed, a weather-resistive barrier (WRB) is applied. Depending on the panel manufacturer and panel type, this may be:

  • House wrap

  • Tar paper

  • A proprietary membrane

Permeability requirements vary by system and climate. Manufacturer specifications must be followed.

Once the WRB (“paper”) is installed, panels can be set.

Roofing Considerations

Your final roof covering—whether asphalt shingles, corrugated metal, or standing seam—may require additional layers or systems, such as:

  • Cold roof assemblies

  • Ventilation mats

  • Secondary membranes

These requirements vary by manufacturer and roof type. Following manufacturer recommendations is critical to:

  • Preserve warranties

  • Avoid condensation and moisture issues

Dry-In Complete

Once panels are installed, and Rough Openings (RO’s) are covered, or the structure is considered dried in. At this point, the timber frame is protected, and interior work can proceed.

In the next post, we’ll cover what happens after dry-in: mechanical systems, electrical, interior build-out, and finish sequencing.