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Conservatory Installation Timeline: Week-by-Week Guide and DIY Options (2026)

From first survey to final inspection: here is what to expect and when.

Updated April 2026.

Full Project Timeline

Survey and quotes (Weeks 1-2)

  • -Initial site visits from 2-3 installers
  • -Measurements, soil type check, access assessment
  • -Written quotes within 5-10 days
  • -Time to compare: 1-2 weeks

Note: Do not accept verbal quotes. Always require a written, itemised quote showing materials, labour, VAT, and any exclusions.

Design, planning, and ordering (Weeks 2-8)

  • -Final design drawings produced
  • -Planning application if required: 8-12 weeks
  • -Building regs application if required: 4-8 weeks
  • -Manufacturing lead time: 4-8 weeks

Note: Manufacturing and planning run in parallel if planning is submitted at the same time as the design is finalised. Total pre-build period: 6-14 weeks.

Base and groundworks (On-site Week 1)

  • -Mark out and excavation
  • -Concrete raft or strip footings poured
  • -7-10 day curing period for concrete
  • -Brickwork for dwarf wall if specified

Note: This is the most weather-dependent phase. Prolonged rain can add 1-2 weeks if the ground becomes waterlogged and the concrete cannot be laid.

Frame and glazing (On-site Week 2)

  • -Sill plates and floor threshold
  • -Frame sections erected and levelled
  • -Roof frame fitted
  • -Glazing panels installed

Note: A lean-to or Edwardian can reach this stage in 3-5 days. A Victorian or P-shaped takes 7-10 days at this stage.

Roof, guttering, and weatherproofing (On-site Week 2-3)

  • -Roof glazing or polycarbonate fitted
  • -Ridge and hip sections sealed
  • -Guttering connected to existing drainage
  • -Flashing to house wall weatherproofed

Note: This is the technically most critical phase - poor flashing is the primary cause of long-term leaks. Insist on lead or GRP flashing, not self-adhesive tape alone.

Electrics, finishing, and snagging (On-site Week 3-4)

  • -First fix electrics (conduit, back-boxes)
  • -Door hardware, handles, locks
  • -Sealant at all joins
  • -Final inspection and snagging list

Note: The Part P electrical certificate should be issued before you complete payment. Ask for it explicitly.

On-Site Build Time by Style

StyleSmall (under 12 m2)Medium (12-20 m2)Large (20+ m2)
Lean-to3-5 days4-7 days5-8 days
Edwardian4-7 days5-10 days7-14 days
Victorian5-8 days6-12 days8-16 days
Gable-end6-10 days7-14 days10-18 days
P-shaped8-14 days10-18 days14-21 days
Orangery3-5 weeks4-6 weeks5-8 weeks

Build time excludes groundworks (concrete curing week), planning/manufacturing lead time, and snagging period.

Base and Foundation Costs

Standard concrete slab and dwarf wall

£1,500 - £3,000

Most common and most cost-effective for level gardens with good soil. A 150mm concrete slab on 75mm hardcore, with a dwarf brick wall to damp-proof course level. Standard for 90% of UK installs.

Engineered concrete raft

£3,000 - £6,000

Needed for clay soils prone to shrinkage and heave, sloping gardens (where cut-and-fill would be substantial), or where ground conditions are uncertain. Requires a soil investigation (£300-£600 extra) to justify the specification.

Screw piles with suspended slab

£2,500 - £5,000

Used where traditional excavation would damage tree roots, disturb services, or where access prevents a concrete lorry from reaching the site. Faster installation than traditional groundworks - piles are installed in a day.

DIY Conservatory Options

A fully DIY conservatory is possible for experienced builders but is not recommended for most homeowners. Here is where the DIY boundary realistically sits.

What You Can DIY (Sensibly)

  • + Base excavation and filling (with correct specification from installer)
  • + Bricklaying for dwarf wall (if you are a competent bricklayer)
  • + Internal tiling and floor laying
  • + Internal decoration (painting, skirting, curtain rails)
  • + Self-build kit assembly (uPVC kit, from £3,000-£10,000)

What Needs a Professional

  • ! Glazing installation (safety glass weight and handling requirements)
  • ! Electrical work (Part P - must be NICEIC or NAPIT registered)
  • ! Roof glazing (falls from height, structural integrity, weatherproofing)
  • ! Connection to house wall (lintel, weatherproofing, damp-proof course)
  • ! Building control sign-off if BR applies

Self-Build Conservatory Kits

Several UK suppliers offer flat-pack uPVC conservatory kits for self-assembly. The kit includes all frame sections, glazing, roof components, and hardware. The buyer completes groundworks and assembly.

Kit cost (3x3 lean-to)£3,000 - £6,000
Base and groundworks (DIY)£500 - £1,500
Electrics (Part P trades)£500 - £1,000
Total DIY kit build (vs £9,000-£13,000 fitted)£4,000 - £8,500

Saving: approximately 30-50% on supply and install. Time cost: typically 2-4 weekends for a small lean-to. Warranty: kit manufacturer's warranty applies only if installed correctly - retain fitting instructions and photograph stages. Suppliers include Conservatory Outlet, SuppliedAndFitted.co.uk, and Diy-Conservatories.com.

How to Vet Conservatory Installers

Trade Body Memberships to Check

GGF (Glass and Glazing Federation)

The primary trade body for conservatory and window installers. Members commit to a Code of Practice and have access to consumer mediation services.

DGCOS (Double Glazing and Conservatory Ombudsman Scheme)

Mandatory dispute resolution scheme for DGCOS members. If your installer is DGCOS-registered, you have access to an independent ombudsman if things go wrong.

FMB (Federation of Master Builders)

General building trade body with a consumer protection scheme and insurance-backed guarantees. Better for larger projects involving brickwork and structural work.

TrustMark

Government-endorsed scheme covering a range of trades. TrustMark installers have been vetted for technical competence and customer service.

Red Flags to Watch For

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Cash-only quotation (no paper trail, no VAT receipt)

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Pressure to commit during the first visit ('price only valid today')

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No written warranty offered or warranty not backed by insurance

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No mention of planning permission or building regulations

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No FENSA or CERTASS certificate offered for glazed units

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No named Part P electrician for the electrics

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Vague quote that does not itemise materials, labour, and VAT separately

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No deposit protection insurance offered on initial payment