Build Process

To view a typical schedule for a construction project open the Excel spreadsheet Construction Programme in the Members Area.

Once all statutory approvals are in place work can begin on site.  Well almost.  First you must check Planning Conditions to make sure that they have all been complied with.   You usually have to inform your planning department when work will commence.

The first task is to put in the track and clear the site.  If you are only using Hebhomes for the supply and erection of the kit this work will be done by your main contractor. 

Setting out the position of the house is next. You may want to ask your engineer to come to site to make sure this has been done accurately as building in the wrong place - or at the wrong height - could upset a neighbour or the authorities,

Once that is done the trenches are dug for the foundations.  Again, you may want your engineer or building control to inspect these.

The concrete strip foundations are then poured to the engineer’s drawings and the underbuild of block (two leafs for a render and block house, one leaf for a timber clad house) are built to dpc level.

The substructure is completed with the hardcore, sand blinding and concrete slab being applied and poured to the engineer's specification.  While this is setting a representative of Hebhomes will visit the site to ensure that the foundations have been built accurately and that the site is ready to take the kit.  This gives the opportunity to either adjust the kit or correct the slab if it is not accurate.  We will also look to ensure the ground is suitable for laying down the kit and manoeuvring the telehandler these around the site.  Generally 2m of compacted hardcore around the perimeter is required.  Restrictions may mean a crane is required or the kit needs to be stored close by.  Constraints can be overcome but may lead to extra costs.

While the foundations are being prepared it is the normal practice to install the sewerage and drainage system.

Next is the arrival of the kit.  Typically, the Hebhomes installation team leader will have coordinated this with the client’s main contractor - presuming this is not a turnkey job.  The erection usually takes around 7 working days for a team of four men, but the time does vary depending on the size and complexity of the kit and the time of year. 

Erection starts with the accurate fixing of the sole plates.  These are timber runners onto which the SIP or CLT walls will be secured.  After the walls and lintels, the metal web joists are bolted, followed by the first-floor waterproof chipboard flooring.  The ridge is the craned into place and the roof panels carefully screwed, nailed and glued as the engineer's fabrication drawings.

Internally Hebhomes will fit VC foil as the specification and externally the thick protective membranes on the walls and roof. Non-load bearing walls will now be erected and finally the windows installed. 

The house is now 'wind and weathertight' and ready for being inspected and handed over.  It should be noted that the rooflights will not be fitted at this stage as this may lead to water ingression.  The rooflights are fitted with the flashings by the main contractor when the slating or application of the metal sheeting is in progress.

It should also be remembered that 'wind and weathertight' does not mean that water will not ingress into the building especially in wet and windy Scotland.  A building will only be completely protected from rain once the exterior claddings and silicons are completed. 

The Supply and Erect contract from Hebhomes is now over.  

Since the scaffolding is stillup the roof  completion is next, first with battening and then profiled metal sheeting or slates most typically.  At the same time roughing joinery work can start, with battening and framing to the walls internally.

Once the basic internal roughing is completed the electrician starts his work, running wiring through the house.  The plumber follows shortly after, with the joiners continuing their work throughout this period. This is when the underfloor heating pipes are run over floor insulation and set within 70mm screed.  It may be the case that the pipes have been set in the structural slab depending on the floor build-up. The first fix of the MVHR also proceeds.

After the first fix plumbing and electrics, as well as all the sound insulation being fitted, the joiners fit the plasterboard through the house.  Different plasterboard is used depending on requirements: sometimes insulated plasterboard to the exterior walls, red fire resistant plasterboard behind the stove, green water resistant plasterboard in the bathrooms and thicker plasterboard to the ceilings to minimise sound transfer. 

Taping and filling now commences.  Throughout this period work would have also been continuing outside with either the fitting of the battens and timber cladding or the outer leaf of blockwork.  The rendering of the blockwork will be weather dependant. 

After taping and filling (in England the tradition is to plaster the entire wall) the joinery finishings can start.  This means hanging doors, skirtings, architraves etc.

The plumber soon returns to begin the second fix of plumbing work and will soon be joined by the electrician.  This is when complex elements such as the air source heat pump are installed and connected.  The MVHR will also be completed. The joiners will also be on hand to help.

Now the kitchen is being installed, the floor is being laid, the tiling is being done and the bathroom furniture hung.  The site has never been busier.  Outside the gutters are fitted and connected to the drainage system.

Completion Day is approaching.  The decorators are meticulously painting the house and the outside is being landscaped with the gravel laid on the road and the entrance tarmaced.  

Throughout the 6 -8 months it takes to build a house in rural areas, the contract between the client and the contractor should have been administered by an industry professional.  It is usual for a Small Works contract to be used on a domestic house and for the contractor to be a local architect or quantity surveyor.  Their role is to make sure that the client only pays for work properly carried out.  Valuations are every 4 weeks and there is a retention of 5% of the value of the main contractor’s contract throughout the build period.  When the administrator decides that Practical Completion has been reached, the keys are handed over to the client and half the retention is paid.  This is also the time that the client has to insure their own house.

In the case of turnkey from Hebhomes NHBC warranties will be provided and the Completion Certificate supplied by the council. With your own main contractor the administrator will either provide certification on the house or have arranged a warranty. 

During the next year and latent defect which become apparent are recorded.  These will be made good at the end of the defect period unless they interfere with the enjoyment of the house.  Then they should be rectified at the earliest opportunity. The final 2.5% rentention is then paid.

It should be remembered that the project manager during the build period is the main contractor.  It is their job to coordinate and ensure people and materials arrive on time and in the correct sequence.  It is their job to ensure the houe is finished by the completion date in the contract. 

It is the job of the contract adminstrator to ensure that the terms of the contract are met and that money is paid for work properly carried out.  They will also record any variations that have been instructed and decide on requests for extention of time and additional costs. Minor Works contracts are fixed priced contracts and extra costs will only arise if the client instructs a variation (changes something), an item costs more than what was allowed within the contract (a provisional sum) or if the contractor is due extra money for an unknown (rock-breaking for example). 

There are provisions for liquidated damages in the Minor Works contract. These are useful if a completion date by a certain time is essential - for example if your house must be ready for letting.  The figure inserted has to reflect actual loss and it should be anticipated that a contractor will normally increase his price to cover the risk if this clause is utilised. 

If you have decided to organise the trades yourself then you are effectively the main contractor.  This means organising site provisions, insurances, materials and subcontractors.  Substantial savings can be made but it is time consuming and can be difficult and stressful if you lack experience.