Technical Design & Tender Documentation in London

Tendering is the stage where a design becomes a price. If contractors price from inconsistent or incomplete information, their quotes are not comparable and the cheapest number often hides the most assumptions. A coordinated tender package lets you compare builders on a like-for-like basis and gives the successful contractor clear information to build from, reducing variations and disputes.

We develop the design into coordinated technical information, integrating structural and other consultant input so the package holds together, and set out an outline specification appropriate to the project so the quality you expect is priced from the start. We then issue it to a selected list of contractors, manage their queries during tender, and help you review the returns.

A tender package is more than a set of drawings. It brings together the construction drawings, a specification describing materials and standards of work, schedules of finishes, windows and doors, and a clear definition of the scope and any preliminaries — so every contractor is pricing the same defined project. The completeness is the point: where the information is vague, builders price their own assumptions, and the returns become impossible to compare. A well-assembled package is what turns tendering from a guessing game into a genuine comparison.

Who you invite matters as much as the package itself. We help you draw up a sensible tender list — contractors of the right size and experience for the project, ideally with references and a track record on comparable London homes — rather than simply gathering the cheapest names. Inviting a handful of genuinely suitable builders to price the same information produces realistic, comparable bids and a contractor who actually wants the work, which is worth far more than a long list chasing the lowest number.

The lowest figure is rarely the whole story. We help you read the returns properly — normalising the quotes onto a like-for-like basis, identifying exclusions, provisional sums and assumptions, and checking that the cheapest bid has not simply left things out that will reappear as expensive variations later. The aim is to choose the contractor offering the best value and the most realistic price for the defined scope, with a clear understanding of what each tender does and does not include.

Planning drawings show what a building will look like. They do not define insulation build-ups, steel sizes, window ironmongery, bathroom waterproofing or the exact extent of making-good. When three builders price from that level of information, they invent three different scopes — and the cheapest quote is often the least complete. A technical design and tender package replaces guesswork with one defined scope: coordinated drawings, specification notes and schedules every tenderer prices against.

That package usually builds on building regulations drawings and structural engineer information. The aim is comparable tenders and fewer mid-contract variations, not a thicker set of pretty sheets.

A typical residential tender set includes general arrangement plans, elevations and sections at construction level, key construction details, door and window schedules, finishes intent, and an outline specification that states performance where products are not yet chosen. Provisional sums are labelled honestly where client choices (kitchens, sanitaryware, specialist finishes) remain open. Structural drawings and calculations sit alongside so builders are not guessing steel weights.

We advise how many contractors to invite and how to run a clear tender period with a single query log, so every bidder sees the same answers. After return, we help you compare like-for-like rather than headline totals alone.

Once a contractor is selected, the same information base supports the building contract and site queries. Optional next stages include contract administration or lighter construction-stage architectural support. Choosing the right level of post-tender involvement depends on project value, complexity and how much risk you want professionally managed during the build.

We scope that choice in writing so tender documentation does not quietly expand into full site duties without agreement.

Building control and tendering run in parallel, and they ask different questions of the same drawings. A building control body is judging the design against the Approved Documents rather than pricing it: structure under Part A, fire safety and escape under Part B, ventilation under Part F, stairs and guarding under Part K, energy and fabric performance under Part L and electrical work under Part P, with overheating under Part O engaged only where the work creates a new dwelling rather than extends an existing one. A full plans submission gets that judgement in writing before anyone starts, whereas a building notice defers it to inspection on site, which sits badly with a fixed price: a builder told at first fix that a detail must change has a variation, not a quote. We would rather the building control application is settled, or at least submitted, before contractors price.

The other half of the job is turning those requirements into words a builder can price. Insulation continuity and airtightness, the ventilation strategy, glazing and shading where overheating matters, fire-rated construction and protected escape in a loft, acoustic separation between flats: if these sit only in a consultant's report, the cheapest return is usually the one that assumed the least, and the gap reappears when an inspector asks for what was always required.

Planning permission rarely arrives unconditional, and the conditions attached to it shape what a builder is allowed to do. Pre-commencement conditions calling for material samples, large-scale joinery details, a construction logistics statement or tree protection have to be resolved before work starts, and the drawings they call for are design work, not something to hand the contractor on day one. Tenderers should also know which conditions are still live, because an approval covering brick, mortar or window sections limits what they can substitute. Where the design has developed since consent, the priced scope still has to match the permission you hold, so we flag anything awaiting discharge in the package.

Neighbours and landlords add constraints of their own. Excavating near a boundary or cutting into a party wall means serving notices that run statutory periods of one or two months, and the award that follows can fix working hours, monitoring, protective works and access, all of which a contractor has to price. In a flat, the freeholder's licence to alter may add insurance requirements, protection of common parts and rules about how materials move through it. Add the London realities of no parking, nowhere to store anything and scaffolding that needs a neighbour's permission, and preliminaries can move a return further than the finishes do.