A complete technical planning system for serious builders. Developed from Nordic construction standards and real-world sauna engineering — not assembled from forum posts and intuition.
Most DIY sauna builds proceed from aesthetics backwards. They start with the visual — the cladding, the bench, the heater — and treat the structure underneath as an afterthought. This is exactly why so many fail. A sauna is a thermally active, high-humidity enclosure. Every layer of its construction must be intentional.
Reversed or incomplete insulation sequences create thermal bridges that reduce efficiency and allow progressive moisture infiltration into the wall cavity — often undetectable until the frame is compromised.
Poorly positioned supply and exhaust openings destroy the convective heat column. The result is uneven temperatures, stagnant air at bench level, and a sauna that never reaches a functional löyly despite adequate heater output.
Selecting a heater based on manufacturer wattage claims alone — without calculating for glass area, external wall exposure, ceiling height, and air volume — produces a unit that cannot reach correct operating temperature.
A vapour barrier installed on the wrong side of the structure traps condensation within the wall assembly. This damage is invisible behind the cladding for 18 to 36 months — and by then, a full internal rebuild is required.
Insufficient clearances around electric or wood-burning units, incorrect flue routing, or combustible material proximity are the primary causes of sauna fires. These are preventable failures with correct specification at the planning stage.
Without a build sequence and a documented specification list, most projects run 30 to 60 percent over initial estimate through rework, incorrect purchases, and structural corrections — all of which were avoidable.
Moisture damage behind cladding becomes visible only after it has moved through the insulation and into the structural frame. A ventilation error costs nothing on the day of installation — and thousands to correct once the build is finished and tiled.
| Mistake | Typical Cost | What It Actually Involves |
|---|---|---|
| Moisture remediation — full internal strip and rebuild due to vapour barrier failure | €3,800–6,200 | Disposal, replacement insulation, new vapour barrier, re-cladding. Labour additional. |
| Heater replacement after incorrect sizing — second purchase and second installation | €1,400–2,400 | Wrong unit disposed of. Correct unit sourced, delivered, and wired by a certified electrician. |
| Ventilation correction — re-routing supply and exhaust after tiling is complete | €600–1,800 | Tile removal, new penetrations, sealing, re-tiling. Near-impossible without full surface work. |
| Specialist contractor day rate to correct structural errors post-build | €650–950/day | This is the cost of correcting work that should not have occurred. No added value, only remediation. |
| Project delay — rework, re-ordering, re-certification | 6–14 months | Average delay recorded across European correction projects. Not including client relationship cost. |
These are not worst-case scenarios. They are the standard outcomes of a build that proceeded without a correct technical framework. The materials exist in almost every hardware store. The knowledge of how to use them correctly is what is missing.
The SaunaAgent™ Blueprint was developed as a technical decision framework — the kind used by Nordic sauna contractors who plan multiple builds per year and operate to a standard that allows no structural ambiguity on site. Every recommendation has a reason. Every specification is derived from Finnish building logic, thermal physics, and documented project experience across the European market.
The Blueprint does not replace professional judgment. What it does is transfer the reasoning of experienced sauna engineers into a structured format that a competent builder, developer, or informed homeowner can follow with confidence — and know at each stage why they are making the decision they are making.
"The difference between a sauna that lasts thirty years and one that fails in three is not the quality of the timber. It is whether each layer of the wall was placed in the correct order, for the correct reason."
SaunaAgent™ gives you that reasoning. Documented. Referenced. Ready to apply to your project from day one.
Every module explains the why behind each specification — not just what to do, but what happens structurally and thermally if you do otherwise.
All specifications are grounded in the Finnish building tradition that has produced functional, durable saunas for generations across the most demanding climates in Europe.
The Blueprint covers the full range of build contexts encountered across the UK and European market, with specific guidance for each scenario.
Each module addresses a discrete phase of the sauna planning and build process. Read in sequence for a new project, or consult by module for a specific decision mid-build.
The correct construction sequence for thermally efficient, moisture-resistant sauna walls — for both timber frame new-builds and internal conversion scenarios.
The single most misunderstood element in sauna construction. Placed correctly, it protects the structure for decades. Placed incorrectly, it traps condensation from the first use.
The ventilated cavity behind sauna cladding is not an optional detail. This module covers the dimensional requirements and drainage logic that prevent moisture accumulation at the base of the wall.
A sauna requires a specific air change logic that differs fundamentally from standard room ventilation. Position and sizing of supply and exhaust openings determines whether the heat column is functional or not.
Heater selection is not a catalogue decision. It is a calculation. This module provides the full methodology for determining correct heater output for any sauna room.
Bench design determines the thermal experience. Height, depth, pitch, and inter-bench clearance are precise values in Finnish sauna tradition — and they are grounded in the physics of radiant heat.
The sauna is a high-humidity, high-temperature environment. Electrical installation requirements differ significantly from standard residential work. This module covers the non-negotiable safety criteria.
Not every timber performs the same in a sauna environment. This module provides a structured guide to material selection for cladding, benches, framing, and floor finishes.
An outdoor barrel sauna and an internal room conversion share the same thermal logic but differ in almost every construction detail. This module covers both scenarios with specific guidance for each.
A consolidated reference checklist of the 24 most frequently encountered errors in European sauna builds — drawn from real correction projects. Use it to audit a build at any stage.
A single day of specialist remediation work in Northern Europe costs between €650 and €950. A moisture rebuild averages €4,200. A heater replacement runs €1,400 to €2,400. These are not hypothetical figures — they are the documented costs of preventable planning errors.
Average cost to strip, replace insulation and vapour barrier, and re-clad a 6m² sauna room after moisture damage from an incorrectly placed vapour barrier. Labour not included.
10 technical modules. Heater sizing calculations. Vapour barrier logic. Ventilation design. Electrical safety reference. Material selection guide. Common mistakes checklist. One document. One decision.
Day rate for an experienced Nordic sauna consultant to review your plans and specifications. Appropriate for complex commercial projects. For a single domestic build, the Blueprint covers the same technical ground.
Download the SaunaAgent™ Blueprint today. Plan your build with the technical rigour of a professional Nordic sauna engineer — from the first structural decision to the final pre-commissioning check.
Download the SaunaAgent™ Blueprint — €97Is this Blueprint suitable for someone with no prior sauna construction experience?
Yes, provided you have a baseline level of construction competence. The Blueprint assumes you understand how a building is put together — stud walls, insulation layers, basic electrical principles. It does not assume prior sauna knowledge. Each module explains the technical reasoning behind the specification, so you can follow the logic even if you are encountering these concepts for the first time. If you have no construction background at all, the Blueprint is better used as a tool for briefing and managing contractors than as a hands-on build guide.
Does the Blueprint cover both indoor and outdoor sauna builds?
Yes. Module 09 is dedicated to the distinction between indoor conversions and outdoor new-build scenarios, covering the specific structural, drainage, weatherproofing, and planning considerations for each. The core technical modules — insulation, vapour barrier, ventilation, heater sizing — apply to both contexts, with scenario-specific guidance noted where the approach diverges.
Is the Blueprint specific to any country's building regulations?
The Blueprint is based on Finnish building standards (SFS) and Nordic construction logic, which form the most rigorous and widely referenced baseline for sauna construction in Europe. The technical specifications apply broadly across the UK and EU market. However, local building regulations vary. For projects requiring planning permission or building control sign-off, you should always verify the specifications against your local authority's requirements. Module 09 includes a general reference to planning and regulation considerations by region, but the Blueprint does not constitute a legally compliant specification document for any specific jurisdiction.
Can contractors and developers use this Blueprint commercially?
Yes. The Blueprint is designed for use by construction professionals as well as informed owner-builders. Contractors use it as a specification reference and client communication tool. Developers use it to brief build teams and evaluate contractor proposals. The licence included with purchase covers personal and professional use for the individual purchaser. If your organisation requires multi-seat or team licensing, contact us directly before purchase.
What format is the Blueprint delivered in, and how do I access it?
The Blueprint is delivered as a PDF document with accompanying reference sheets. Upon completing your purchase, you will receive an immediate download link and a confirmation email with a permanent access link. The PDF is formatted for both screen reading and high-quality print. There are no apps, logins, or subscriptions required. All future revisions to the Blueprint are included with your purchase and will be delivered via the same access link.