Running Compressed Air To A New Building Or Extension

Running Compressed Air To A New Building Or Extension is a pressure-system modification, not a plumbing job. In the UK, it can trigger a PSSR 2000 review before go-live, and the decisions made on pipe size, ring main layout, drainage and filtration decide whether the new building reduces losses or locks them in for years.

Control Gear Group, specialists in compressed air and industrial equipment, has worked from South Wales since 1973, supporting factories across South Wales, the West of England and surrounding regions. This guide explains the legal, safety and design checks we’d expect before extending any industrial compressed air network.

Why Extension Planning Changes the Whole Air System

Extending a compressed air network changes demand, pressure loss, stored energy and point-of-use quality, so the design has to be treated as a whole-system change before the first pipe is installed.

The financial case is blunt. The Carbon Trust (carbontrust.com) reports that compressed air accounts for around 10% of UK industry’s electricity consumption, and a single 3mm leak can cost over £1,000 a year in wasted electricity.

Most facilities teams think they’re paying their electricity tariff at the tool. They’re not. The BCAS energy efficiency guide (bcas.org.uk) states that as little as 8% to 10% of the electrical input becomes useful work at the point of use.

Cost And Design Impact

That’s why compressed air is often cost at about 50p/kWh in practice. Once the extension is live, every undersized section, leaking joint and restrictive outlet keeps charging that rate.

If the new building is treated as spare capacity on the existing network, the compressor room pays for that shortcut long after the installation invoice has been filed.

The Legal Trigger Before Go-Live

Regulation 8 requires a suitable written scheme of examination before qualifying pressure equipment is used, and a building extension can require that scheme to be reviewed before the modified system is brought into service.

The Health and Safety Executive (hse.gov.uk) defines relevant fluid to include compressed air above 0.5 bar above atmospheric pressure. It also states that formal examination documentation must be in place before using qualifying pressure equipment, whether the equipment is new or existing.

Regulation 7 And Regulation 8 In Practice

Regulation 7 of PSSR 2000 legislation (legislation.gov.uk) requires safe operating limits to be established. Regulation 8 covers the inspection plan, which is where the competent person decides what needs inspection, how often and under what conditions.

Running a new line to another building changes the distribution system. If you add an air receiver, alter protective devices, extend associated pipework or change the operating pressure, the written scheme of examination has to reflect the modified risk.

Planning The Review Early

BPG 101-6 is the other reference we’d expect engineers to use. The trade body describes it as a 272-page installation guide covering specification, installation, maintenance and end-of-life removal.

Where compliance is left until commissioning week, the legal issue arrives at the same time as production pressure. It’s much cleaner to involve the competent person before the final route, receiver position, isolation points and relief protection are fixed.

Air Compressor Pipework Installation: Sizing, Velocity And Equivalent Length

A pipe run is not measured by straight distance alone. Every bend, tee, hose coupling, filter and valve adds friction, and that friction has to be counted before the extension pipe size is confirmed.

Atlas Copco technical guidance (atlascopco.com) states that fixed distribution networks should be sized so the drop between compressor discharge and the most remote consumption point does not exceed 0.1 bar, or about 1.5 psi. The same design logic is why main headers should run at about 6 to 7 m/s and never above 9 m/s.

Equivalent Length And Pressure Penalty

A 90-degree elbow in a 50mm pipe can add about 1.5m of friction equivalent. Ten elbows add 15m before you’ve counted a single metre of straight run.

That detail matters on an extension across a yard, into a mezzanine or through a roof void. We’ve seen layouts where the drawing showed 40m, but the installed route behaved more like 70m once pipe fittings were counted.

• Measure the straight route to the most remote outlet.
• Add equivalent length for bends, tees, valves, hoses and couplings.
• Calculate peak air consumption for the new process, not average demand.
• Check velocity against the 6 to 7 m/s design range.
• Confirm the final outlet still sits within the 0.1 bar target.

Pressure Cost Of Friction

A manufacturer operating a 200 hp compressor, 24 hours a day, 365 days a year, can’t afford an avoidable 1 bar penalty. The usual rule is a 7% energy increase for every extra 1 bar generated to overcome friction.

Pipe sizing is where the extension either becomes an efficiency project or a permanent running cost. If the calculation is skipped, the compressor may look healthy while the furthest process quietly suffers from pressure loss.

Ring Main Layout, Isolation, and Pressure Control

A closed-loop ring main is usually the right layout for a new industrial extension because air can reach each outlet from two directions. That halves the effective travel distance, reduces velocity and keeps tool pressure steadier during peak demand.

Dead-end linear runs can work for small, low-use branches, but they punish larger installations. If the last workstation needs 6.3 bar under load, a long end-fed branch often forces the whole network to run higher than it should.

Practical Layout And Capacity Checks

For a wider hub-level context, we cover the main system categories on our compressed air page. For this extension decision, the working checks are more specific.

• Fit an isolation valve at the extension inlet so maintenance doesn’t shut the whole factory.
• Use local regulators where the new building has different pressure needs.
• Avoid long flexible hoses as permanent distribution lines.
• Keep access to drains, filters and pressure gauges clear after racking and guarding are installed.
• Leave a measured spare capacity margin instead of guessing from nameplate ratings.

Demand Pattern And Monitoring

Contract Air testimonials in the market often talk about correctly sized systems with VSD Nirvana rotary screw machines, refrigerant dryers, filtration and spare capacity. The lesson is sound even when the brand differs: pressure control has to match the demand pattern, not the sales brochure.

The Internet of Things and IIoT monitoring trend is also relevant here, because connected pressure and flow sensors can expose whether spare capacity is real or only assumed. If the ring main is right but the isolation and regulation are wrong, every maintenance task becomes harder than it needs to be.

Material Selection And The PVC Safety Warning

Standard PVC must not be used for industrial compressed air distribution because it can degrade under pressure and UV exposure, then fail explosively with sharp fragments. Only plastics rated for compressed air service should be considered, and even then, the rating, environment and support method need checking.

Modern extensions have moved toward extruded modular aluminium systems because they’re light, corrosion-resistant and quick to alter. Modular aluminium brands are common in factories where future alteration, low friction and clean installation matter more than the lowest purchase cost.

Aluminium Versus Older Materials

Galvanised steel still appears across older factories in South Wales and the West of England. Once moisture gets inside it, the zinc layer degrades, rust forms, the bore roughens and downstream filters start catching pipe scale.

Modular aluminium systems are often chosen where future extension is likely, because they are easier to alter, keep internal friction low and avoid the corrosion issues associated with older steel pipework.

Material choice affects pressure loss, contamination and future alteration, so it belongs in the design meeting rather than the purchasing queue.

Condensate, Gooseneck Drops and Air Quality

Water management is part of the extension design, not a commissioning afterthought. A typical 100kW compressor can produce up to 85 litres of condensate per shift in UK conditions, and that water carries oil, rust and dirt through any poorly drained branch.

Never tap a drop leg from the bottom of the main header. Bottom tapping sends condensate and scale directly into tools, valves and FRL units.

Gooseneck Drops And Drainage

Take the branch from the top or side of the header, then drop down to the point of use. That gooseneck arrangement keeps liquid in the main line until it reaches a drain leg, instead of feeding it into an actuator or spray tool.

• Slope main lines by 1/8 to 1/4 inch per foot in the direction of airflow.
• Put drain legs at low points and before vertical rises.
• Use zero-loss drains where air loss from timer drains is costing money.
• Fit point-of-use treatment only where the process needs a higher class.

Air Quality Classes

Air quality in the new building has to match the job being done there. ISO 8573-1 guidance (airbestpractices.com) classifies particles, water and oil at the point of use, so a packaging line, spray booth and pneumatic tool bench may not need the same class.

Match Classes to Process Risk

Where a new line feeds food, pharmaceutical or cleanroom processes, ISO 8573-5:2025 (iso.org) is now the current oil vapour test method, published in July 2025, using pressurised sampling and gas chromatography. ISO 9001 quality systems may also require documented checks, traceable records and controlled sign-off where compressed air affects product quality.

For ordinary factory air, the larger decision is usually the right combination of dryers, drains and compressed air filters at the correct points. Poor drainage turns a good pipe layout into a contamination problem, and contamination usually shows up first as tool failures rather than lab results.

Leak Control, VSD Demand and Handover Monitoring

A new building should be commissioned with leak targets, pressure readings and baseline flow data, not just a pressure gauge reading at the nearest outlet. Without that baseline, no one knows whether next winter’s higher energy bill came from production growth, leaks or a blocked filter.

The Carbon Trust figure is worth repeating because it changes behaviour: one 3mm hole can cost over £1,000 per year. We’ve visited sites where maintenance wanted a larger machine, then found the air consumption problem was a leak rate close to 30%.

Commissioning Measurements And Baseline Data

A VSD unit can reduce energy use by 20% to 35% compared with fixed-speed operation, where demand varies. But a VSD is not a cure for poor pipework. It saves most when the network is tight, sized correctly and not being held at excess pressure to cover a distant restriction.

• Record pressure at the compressor, extension inlet and furthest outlet under load.
• Log flow during normal production, cleaning shifts and peak demand.
• Tag all leaks found during commissioning and assign repair dates.
• Replace failed timer drains, since ten faulty drains can waste measurable flow.
• Review whether 90% of demand could run at a lower pressure zone.

Turning Readings Into Handover Data

Audit worksheets often expose the problem in hard numbers: 5 psig flow reduction, 456 cfm total flow reduction, leak repairs, or replacement of ten timer drains saving 31 cfm. Figures like 184.29kW, 65.75kW and 5kW only help when they’re tied to real operating hours.

Smart sensors have a place here. Pressure, flow, dew point and ambient temperature monitoring can show whether the new branch is drifting away from the commissioning baseline before production starts blaming the compressor.

Energy savings only hold if the handover data gives maintenance something to compare against.

Case Evidence And Commissioning Checks

The strongest extension designs are boring at handover: stable pressure, dry drops, labelled isolation, current examination records and no surprise demand spikes. That’s what good commissioning should produce.

In practice, replacing undersized linear pipework with a correctly sized modular aluminium ring main can materially reduce pressure drop and allow a lower compressor set-point, which improves system efficiency across the wider network.

Final Production Sign-Off

Use the commissioning stage to prove the new area is ready, not to discover whether the installer got away with it. In our view, the minimum pack should cover legal, mechanical, energy and quality checks.

• Written scheme of examination reviewed by a competent person where required.
• Regulation 7 safe operating limits confirmed and marked.
• Pressure readings taken at the compressor, inlet and remote outlet.
• Drain legs checked with the line under real load.
• ISO class confirmed for any process that touches product, packaging or breathing air.
• Leak survey completed after the system has been pressurised.
• User training completed for isolation, drains and prohibited use.

Safety Checks By Application

For hygienic extensions, the article on how to avoid microorganisms in compressed air is a relevant background because moisture and microbial growth are linked. For construction or tooling areas, safety moves toward guards, couplings, whip checks and tool ratings.

The ISO 11148 series (iso.org) covers safety requirements for hand-held non-electric power tools, including pneumatic tools. US OSHA 1910.242(b) (law.cornell.edu) is not UK law, but its 30 psi cleaning limit is often cited because it captures the same hazard: high-pressure air is dangerous when misused.

If the extension is signed off without those checks, the first production fault will send everyone back to the design decisions that should have been challenged earlier.

FAQ

The questions below cover common buyer checks that come up before an extension, especially where compressed air feeds construction tools, production equipment or cleaning stations.

Use limits affect cleaning, personnel safety and dust exposure. Building services affect distribution pressure, filtration and stored energy. Legal checks affect scheme documentation, examination scope and safe operating limits.

• Personal safety: Never direct compressed air at skin or clothing.
• Building supply: Size pipework for flow, quality and pressure at the point of use.
• Legal control: Review compliance records when stored energy or examination scope changes.

For What Purpose May You Not Use Compressed Air?

You must not use compressed air to clean skin, clothing or loose debris from a person. It can drive particles into tissue, damage hearing and inject air into the bloodstream. For bench cleaning, use controlled low-pressure equipment, guarding and PPE, or choose a vacuum method where dust exposure is the main risk.

What Does an Air Compressor Do for a Building?

An air compressor supplies stored pneumatic energy to tools, actuators, valves, spray equipment and production machinery in the building. It draws in atmospheric air, compresses it to a set pressure, then sends it through receivers, dryers, filters and distribution pipework so each point of use receives the required flow and quality.

What Is Compressed Air Used for in Construction?

In construction, compressed air is used for breakers, nailers, drills, pumps, shot blasting, paint spraying and temporary pneumatic controls. The supply must match tool flow, pressure and duty cycle. Hoses, couplings and whip checks need inspection because construction use adds movement, impact damage and contamination risk.

What Are The Safety Requirements for Compressed Air?

Safety requirements include pressure-rated pipework, suitable relief protection, isolation valves, guarded couplings, trained users, documented safe operating limits and a current written scheme of examination where the rules apply. Air quality must match the application, and pneumatic tools should be used within their rated pressure and relevant ISO 11148 safety requirements.

When Does an Extension Need a Written Scheme Review?

An extension needs review when the pressure system changes in a way that affects safe operation, examination scope or stored energy risk. Running air to another building, adding a receiver, altering protective devices or changing pressure limits can all trigger that review before go-live. The competent person decides the final scope.

If you’re planning a new production area in South Wales, the West of England or the surrounding regions, speak to Control Gear before the pipe route is fixed. We can review the extension layout, check the legal position and size the system before avoidable losses become part of the building.