TruHomes

Standard Specification Timber Frame Design Work

Tru-Homes provide:

A base plan and soleplate layout drawing for the client / builder to check the base.

Timber frame layout drawings and details for client approval prior to manufacturing the frame.

Timber frame construction drawings and typical details for the erection team.

Timber frame engineering calculations supplied to the client for Building Regulation submission.

Roof truss and floor joist calculations if applicable / required.

NHBC HB 353b Certificate if required.

Chain of Custardy certification for timber supplied if required by the client.

Six year, insurance backed, structural warranty with supply and erect packages.

Timber Treatment

All solid timber that is used as wall panel studs, lintels and head binders, solid timber floor joists, metal web joists, roof trusses and cut reafters is Vacsol Aqua treated. This is an environmentally advanced water based preservative treatment with bio-degradable active ingredients. With a sixty year service life Vacsol Aqua treated timber is your insurance against fungal decay and insect attack.

Soleplates are pressure treated using Tanalith E, a waterborne product based on copper triazole technology.

Timber fascias, bargeboards and T&G soffits are vac-vac treated.

DPC’s.

600mm wide polythene dpc to external ground floor wall panel soleplates.

300mm wide polythene dpc to internal ground floor wall panel soleplates.

Timber Frame External Wall Panels.

Panel studs, top and bottom rails to be 140mm, 184mm or 235mm x 38mm.

Timber frame wall panels constructed using I section studs, and top and bottom rails can also be offered to the client looking for an exceptionally well insulated home. 240mm, 300mm and 360mm x 45mm stud sizes are available.

Panel junctions that are inaccessible post erection are insulated in the factory.

External face sheathed using 9mm WBP plywood.

Housewrap breather membrane, or the higher performance Tyvek Reflex membrane factory fixed to the external sheathing boards. Stud positions are marked using polypropylene tape, fixed using stainless steel staples.

Standard panel heights are 2400mm, other sizes are quoted for as called for by the building’s design.

Timber Frame Internal Wall Panels.

Internal wall panels are generally constructed using 90mm x 38mm treated timber.

Other stud sizes are provided if required by the building design.

Racking panels are sheathed on one face with 9mm plywood.

Party walls are fully sheathed on the cavity face with 9mm plywood to provide Robust Detail Type E-WT2. Cullen- bp Acoustic Straps are fitted at 1200mm centres to allow for the transfer of racking between dwellings whilst maintaining the correct cavity width.

Load bearing internal wall panels have mid height noggins factory fitted if required by the engineer.

Joist Platforms.

Within our quotes we provide costings for two different types of floor joists; timber engineered Steico I joists and metal webbed Gangnail Ecojoists which we manufacture in our Exeter factory.

The size and depth of joist is as determined by the design and engineer.

The joist platform ring beam is 44mm whitewood Glu-lam so as to minimise shrinkage.

An Airguard membrane is lapped around the perimeter of the ring beam to provide a higher degree of air tightness.

All timber and steel beams within the flooor zone are included within our quotations.

21mm T&G WBP flooring grade plywood, screwed to the joists, with the joints glued using waterproof adhesive.

Stairwells are temporarily trimmed with plywood over. This is done for site safety.

Blocking between joists is supplied and fixed under internal wall partitions.

Roof Structures.

All types of roof truss, standard fink trusses, raised tie, mono and attic trusses are designed and manufactured in our Exeter factory.

We use treated timber as standard for our trusses.

All bracing and metal work is provided.

If called for by the building design we can manufacture and fix all types of feature trusses, made using Glu-lam or solid timber.

Cut roofs can feature expposed Glu-lam ridge and purlin beams.

Flat roofs are constructed using Steico I joists or solid timber depending on the spans involved.

All steel and timber beams required for the roof structure are included within our quotations.

Plywood sarking is supplied and fixed for cut and flat roof structures.

Gable end roof ladders are delivered to site fully fabricated.

The supply and fixing of timber or UPVc barge, fascia and soffit boards are included within our quotations.

We supply and fix valley boards if required by the roof design.

Dormer window structures ane supplied and fixed.

Roof light positions are trimmed out.

Structural Ancillaries.

Cavity barriers, window and door fixing battens and perimeter firestops.

Party wall fire stops.

Masonry wall ties, supply only.

Qualitherm Package.

In addition to our standard package we also offer clients our insulation package.

As recommended by Trada and the UK Timber Frame Association we do not install insulation in our factory, rather we wait until the building is weather tight and the building’s moisture level is low enough, before installing the wall insulation.

If the insulation were to get wet whilst being stored before delivery to site, whilst being delivered or during the erection process the insulation could degrade due to mould. Once wet insulation can take up to three years to dry out, in extreme cases the insulation would need to be removed and replaced.

The Tru-Homes insulation package includes the insulation of all external wall panels and, if applicable, all party wall panels.

The insulation we use is Knauf Earthwool Flexible slabs. Unlike cheaper roll insulation these cannot slump within the panels, and therefore we avoid the possibility of heat leakage gaps in the insulation.

During the frame erection process we install an Airguard membrane that is lapped around the floor zone perimeter. This membrane is then post erection taped to the internal membrane that is fixed after the insulation has been fitted between the wall panel studs.

A 25mm or 38mm batten is fixed to the studs internally which creates the service void and provides the means to fix the wall boards, by others. Crucially it is the service void which provides the air gap that greatly improves the thermal performance of the wall panel. Having a reflective membrane without the void is a waste of money.

Unconditional Pricing.

One of the key benefits to the client in employing Tru-Homes to provide the timber frame for their build projects is that we will provide the client with an unconditional fixed price quote for the timber frame package, based on drawings that can be accurately scaled.

This gives the client complete confidence in the preparation of their budget. The price we provide is not subject to finalised engineering calculations or incomplete roof and flooring designs.

Crane hire and delivery, even to the most awkward of sites is included within the frame price, as is the services of our dedicated contracts manager.

Attendances To Be Provided By The Client.

Scaffolding and ladders.

If required internal scaffold towers and tresles.

A skip to aid site tidiness.

An electrical supply.

Welfare facilities as required.