DIY Syrup Scale-Up = DIY Ventilation Scale-Up: Lessons from a Food Startup for Home Renovations

Start small, test rigorously, scale sensibly: how a cocktail-syrup startup teaches homeowners to scale DIY ventilation

Feeling the mould on bedroom walls, waking to stale air, or watching energy bills climb after a renovation? You’re not alone. Many homeowners try a single DIY vent or extractor and either under-correct the problem or inadvertently create new ones. The good news: lessons from the DIY growth story of Liber & Co.—the craft-syrup brand that went from a single pot on a stove to 1,500-gallon tanks—map directly onto how you should approach ventilation scale-up in your home. Small experiments, stringent testing, documented processes, and knowing when to hire professionals make the difference between a quick fix and a long-term ventilation success.

"It all started with a single pot on a stove." — the Liber & Co. origin story, a reminder that great systems begin with small, repeatable tests.

Why the analogy matters in 2026

In late 2025 and early 2026 the UK ventilation landscape accelerated: smarter controls, demand-controlled ventilation (DCV), wider consumer adoption of MVHR (mechanical ventilation with heat recovery), and stricter retrofit discipline (notably PAS 2035 for whole-house retrofit projects) changed the stakes for DIY work. That evolution mirrors how a food startup scales: start experimental, validate, document, then invest in larger-capacity infrastructure. For homeowners, that means moving from a single upgrade (a new extractor fan) to a whole-house plan (zonal extract, MVHR, or a hybrid system) only after validated tests and clear performance targets.

Executive summary: the scaled-DIY framework

Apply a four-stage framework modeled on Liber & Co.’s growth:

1. Pilot – start with low-cost tests in the worst rooms (bathroom/kitchen/utility)
2. Measure – track humidity, CO2, and energy impact; set clear go/no-go metrics
3. Refine – iterate on fan sizes, controls, and routing; document what works
4. Scale – move to whole-house upgrades or hire accredited installers for MVHR

Stage 1 — Pilot: the single-pot test for ventilation

Just as Liber & Co. made one small batch to test flavour and process, begin with a contained, inexpensive upgrade:

• Install a quality bathroom extractor on a timer or humidity sensor (if your current fan is old, replace it).
• Add a portable supply/extract fan to an attic or kitchen for a limited trial, or use a temporary window trickle vent for a week.
• Place low-cost IAQ monitors: a CO2 monitor (~£30–£120), a humidity/temperature logger, and a sound meter app for noise checks.

Actionable pilot checklist:

• Buy or borrow: CO2 monitor, humidity sensor, basic sound meter.
• Replace old extractor fans in worst rooms; choose models rated by L/s (litres per second).
• Run the pilot for 2–4 weeks across typical daily routines (cooking, showering, occupancy).

Pilot metrics: what success looks like

• Relative humidity (RH) stays below 60% most of the time; short spikes after showers are acceptable if RH drops back under 55% within 30–60 minutes.
• CO2 remains under 1000 ppm in living spaces during normal occupancy (lower is better).
• Noise from the fan is tolerable—subjective, but measured <35–45 dB(A) for bathrooms is a good target.

Stage 2 — Measure: document, learn, and avoid surprises

Successful scaling is data-driven. Liber & Co. grew by measuring batches, yield, and customer feedback. Your ventilation upgrade must be measured too.

Tools and techniques for robust measurement

• CO2 & humidity monitors: Monitor several rooms simultaneously over multiple days to capture patterns.
• Airflow measurement: Use a simple anemometer or hire a pro for airflow balancing and duct tests. Measure extract rates in L/s.
• Energy and noise: Track electricity use of fans (smart plugs can help) and record noise levels at typical operating positions.
• Visual inspections: Check for condensation on windows, black spots of mould, and smells—these are as important as sensor data.

Decision rules: when to proceed to refinement

1. If humidity drops consistently and CO2 improves, scale the same solution to similar rooms.
2. If individual fixes create negative pressure (doors slamming, backdraughting in chimneys), stop and reassess.
3. If noise complaints increase or energy use rises disproportionately, pause scaling and investigate controls or better equipment.

Stage 3 — Refine: iterate like a food producer

When Liber & Co. increased batch size, they refined equipment and process. In ventilation, refinement focuses on controls, duct routing, and interactions with heating and insulation.

Practical refinements you can do yourself

• Install humidity-controlled fans instead of timers—these reduce runtime and running cost.
• Improve passive air routes by adding trickle vents or transfer grilles so extract fans don’t create excessive depressurisation.
• Acoustic fixes: add flexible ducting with sound attenuators where noise is an issue; ensure fans are mounted on anti-vibration pads.
• Smart controls: implement DCV strategies with CO2 sensors in shared living areas to reduce fan speed when not needed.

When a professional measurement matters

If trial refinements still leave problems—persistent mould in corners, chimney backdraughting, or large pressure imbalances—get a professional for blower-door tests, duct balancing, and combustion safety checks (for homes with open-flued gas appliances).

Stage 4 — Scale: whole-house upgrades and when to hire professionals

Scaling from a single-room fix to whole-house ventilation is where many DIY efforts either succeed spectacularly or fail. The Liber & Co. lesson: invest in the right infrastructure only after small-scale validation and repeatable processes are in place.

Which larger projects are often DIY-friendly and which require pros?

• DIY-friendly (with competence): replacing multiple local extract fans, adding passive vents, installing humidity sensors, and improving trickle ventilation.
• Mixed (depends on skill): duct routing for inline fans, adding short-run supply/extract fans, and upgrading to smart controls—these can be DIY with good planning and electrical competence, but check local regs.
• Professional required: whole-house MVHR installation, complex duct networks, work that penetrates thermal envelopes significantly, and anything impacting combustion appliances or electrical mains. These require accredited installers, building control notification, and certificate of compliance.

Red flags that mean hire a pro now

• Planned work will cross multiple rooms or floors (MVHR).
• Existing condensing boilers, open flues, or gas appliances could be affected.
• There are listed building constraints or significant insulation/airtightness upgrades.
• You're seeking grant funding or want PAS 2035-compliant retrofit planning.

Costing: realistic 2026 UK ranges and budgeting advice

Costs vary by property size and choice of system. Use the following as planning ranges (2026 UK):

• Single bathroom extractor replacement: £80–£400 for a quality fan plus £80–£300 labour if fitted by a pro.
• Several extract fans + controls (kitchen + 2 bathrooms + sensors): £400–£1,200 installed depending on component quality.
• Inline ducted systems for small flats: £300–£1,200 installed each room depending on complexity.
• MVHR whole-house system: equipment £2,000–£8,000; installation and commissioning £3,000–£12,000. Typical total: £5,000–£18,000 depending on property size and complexity.

Tip: Budget for measurement, commissioning and a 2–3 year monitoring period. The cost of removing mistakes (e.g., rerouting ductwork or fixing condensation) can be far higher than incremental testing.

Regulation, compliance and 2026 updates every homeowner must know

In the UK, Part F (ventilation) of the Building Regulations governs performance and ventilation rates for extensions and major works. For retrofit projects, PAS 2035 remains the recognised framework for planning energy-efficiency upgrades, and it explicitly connects ventilation to airtightness and insulation measures. In 2024–2026, industry attention shifted to ensuring ventilation is not an afterthought in retrofit packages—monitoring and post-installation verification are increasingly expected.

Practical implications:

• If your renovation involves increased airtightness, you must upgrade ventilation;
• Some grant schemes and retrofit funds require PAS 2035-compliant assessments and post-installation verification;
• Electrical work must be carried out by a competent person (NICEIC/ registered) and, for more complex systems, installers should be manufacturer-accredited and registered with TrustMark or similar UK schemes.

Vetting installers: the equivalent of a good supplier relationship

Liber & Co. succeeded partly because they controlled supply and held high standards. For ventilation, your installer is the supplier of performance.

Use this vetting checklist with every installer or quote

• Ask for evidence of previous projects similar to yours and request client references.
• Confirm they use correct design methods (airflow calculations in L/s, acoustic estimates).
• Check accreditation: TrustMark, manufacturer-authorised installer lists, PAS 2035 competency where relevant.
• Request a written commissioning and handover report listing measured flows, commissioning results, and control settings.
• Ensure they offer a warranty and a post-installation monitoring/aftercare plan (3–24 months).

Questions to include in your quotation request

1. What brand and model of equipment will be supplied? Provide datasheets.
2. Will commissioning include measured L/s or m3/hr flows and noise readings?
3. How will the installation interact with existing heating/combustion appliances?
4. Who will handle electrical connections—will a registered electrician be used?
5. Is the installer familiar with PAS 2035/Part F requirements if my project triggers them?

Risks and how to mitigate them

Common pitfall: moving too fast. Other risks include creating negative pressure that affects combustion appliances, underestimating noise, and failing to commission correctly.

Risk matrix and mitigation

• Risk: Pressure imbalance causing backdraughting — Mitigation: test pressure differentials, avoid large extract-only upgrades without compensating supply; hire a pro for whole-house work.
• Risk: Condensation in ductwork — Mitigation: use insulated ducts, ensure condensate drains for MVHR units, and follow manufacturer guidance.
• Risk: Excessive noise — Mitigation: choose low-Sone fans, use anti-vibration mounts, and check decibel levels during commissioning.
• Risk: Non-compliance with regulations — Mitigation: consult building control, use accredited installers, and retain test records.

Real-world mini case study (composite example)

Homeowner: 3-bed semi with recurring bathroom mould after a 2024 loft conversion that improved airtightness.

1. Pilot: replaced old bathroom fan with humidity-controlled unit and added CO2/humidity monitors in living room and bathroom.
2. Measure: RH dropped from sustained 68% to peaks of 58%, CO2 in the lounge fell from 1,200 ppm to 850 ppm during evenings.
3. Refine: added passive trickle vents to bedrooms and a transfer grille under the living room door.
4. Scale: after proving metrics, homeowner commissioned a pro to install a small MVHR for the whole house—costs shared by an energy-efficiency grant—and got a PAS 2035 assessment included in the quote.

Result: mould gone, comfort improved, and energy bills neutral to slightly lower due to heat recovery and better controls.

Advanced strategies & 2026 trends to consider

• Demand-Controlled Ventilation (DCV): CO2-based or occupancy-based ventilation is now mainstream in 2026—smart sensors reduce runtime and energy use.
• Hybrid systems: combining intermittent extract with MVHR or zoned supply can be cost-effective for some homes.
• Digital commissioning: expect installers to provide downloadable commissioning logs and remote monitoring options as part of premium packages.
• Grant and retrofit linkage: more funding schemes are conditioning support on verified ventilation upgrades post-retrofit—document everything.

Actionable step-by-step plan for your next 90 days

1. Week 1: Purchase CO2 and humidity monitors; replace the worst bathroom fan with a humidity-controlled unit.
2. Weeks 2–4: Run monitors through typical activity; record peaks and durations. Note noise levels subjectively and with a decibel app.
3. Weeks 5–6: Implement simple refinements (trickle vents, transfer grilles) and retest.
4. Weeks 7–10: If metrics improved, request 2–3 quotes for scaled solutions (zoned extracts or MVHR). Use the vetting checklist above.
5. Week 11–12: Select installer, confirm commissioning deliverables, and schedule installation. Arrange monitoring for the first 3–12 months post-install.

Final takeaways — the Liber & Co lessons applied to ventilation

• Start small: a low-cost pilot reduces risk and informs design.
• Measure everything: objective data beats guesswork—humidity, CO2, airflow and noise are your KPIs.
• Iterate and document: keep records so installers can scale a proven solution rather than guessing.
• Know your limits: full-house MVHR, complex ducting or anything affecting combustion safety should be done by accredited professionals.
• Plan for compliance: building regs, PAS 2035, and warranty/commissioning requirements are part of the solution, not an afterthought.

Call to action

If you're ready to move from pilot to scale, our UK installer directory lists vetted, manufacturer-accredited ventilation professionals who provide transparent quotations, commissioning reports, and post-install monitoring options. Start by downloading our 90-day checklist and request three written quotes using the vetting questionnaire above—book a free consultation with a ventilation specialist today to turn your small wins into a whole-home solution.

Related Reading

• Compact Home Repair Kit (2026): build a portable, future-ready fix-it pack
• Portable Power Stations Compared: Best deals and when to buy
• Observability & Cost Control for Content Platforms: a 2026 playbook (useful for monitoring plans)
• Hands-On: In-Wall Smart Surge Protectors & Load Monitors for Everyday Homes (2026)
• 5 Dessert Classics (Like Viennese Fingers) and How to Make Them Pipeable Every Time
• Cashtags, Live Badges, and the New Language of Small-Cap Investing on Bluesky
• Netflix’s 45-Day Promise: What It Would Mean for Our City’s Independent Cinemas
• Credit Unions, Brokerages and Hotels: How New Partnerships Are Reshaping Travel Marketplaces
• Non-Alcoholic Pairings for Steak: Mocktails and Syrup-Based Drinks for Dry January (and Beyond)