Oil-Based vs Water-Based Paint: A Practical Guide for London Properties

Oil-Based vs Water-Based Paint: What London Homeowners Actually Need to Know

The question of oil-based versus water-based paint comes up in almost every client conversation we have about decorating period properties. The short answer is that both have their place, neither is universally superior, and the right choice depends on what you're painting, what finish you want, and how you're living in the property while the work is being done.

Here's the longer, more useful answer.

What the Terms Actually Mean

Oil-based paints use an alkyd or linseed oil medium as the binder. This medium gives the paint film its durability, its hardness when cured, and its characteristic slow drying time. Gloss, eggshell, and satinwood in traditional formulations are all oil-based. They're thinned with white spirit and cleaned up with white spirit or turps.

Water-based paints use an acrylic or vinyl polymer as the binder, dispersed in water. Emulsions are water-based. So are the newer generation of acrylic eggshells, satinwoods, and gloss paints that have largely replaced traditional oil-based products in domestic use over the past fifteen years. They're thinned with water and clean up with water.

The distinction matters because the two systems behave differently in application, in drying, in the finished film, and in long-term performance.

Drying and Curing Times

This is where the practical difference is most immediately felt. Water-based paints dry to the touch quickly — often within 30–60 minutes — which means you can apply multiple coats in a single day. Oil-based paints can take 12–16 hours between coats, and require good ventilation to cure properly.

However, and this is important: drying and curing are not the same thing. A water-based eggshell might feel dry in an hour, but it doesn't reach its final hardness for several weeks. During this curing period, it's vulnerable to marks, abrasion, and scuffs. Oil-based finishes also cure slowly, but once cured they tend to be harder and more resistant to physical damage.

In a busy London household, the long curing time of water-based finishes can be a problem. Kitchen units repainted in water-based eggshell need to be treated carefully for at least four weeks after finishing. In a period property hallway where coats, bags, and shoes are constantly making contact with joinery, a water-based finish will show wear sooner than an equivalent oil-based one.

VOC Levels and Living With Paint Smells

VOC stands for volatile organic compounds — the solvents that evaporate from paint as it dries. Traditional oil-based paints have high VOC content. The white spirit carrier evaporates over hours and days, producing the characteristic paint smell. In a well-ventilated room this dissipates quickly; in a tightly sealed modern flat it can be much more noticeable.

Water-based paints have significantly lower VOC levels — many are classified as low-VOC or even zero-VOC — and the main carrier is water, which produces no harmful vapour. From a health and indoor air quality perspective, water-based systems are significantly better, particularly in properties where residents are staying during the work.

This consideration often tips the decision for us when clients are living in the property. For unoccupied properties, or for commercial spaces where we can ventilate properly, oil-based products remain a strong choice where their performance advantages are relevant.

Where Oil-Based Paint Still Wins

Despite the industry's general move toward water-based systems, there are still applications where oil-based paint is the better choice:

Bare or previously oil-painted timber joinery. On skirting boards, architraves, and window frames that have been properly stripped and primed with an oil-based primer, the subsequent coats of oil-based eggshell or gloss will flex with the timber through seasonal movement in a way that harder acrylic films sometimes don't. This is particularly relevant in period properties where the joinery is softwood that expands and contracts significantly.

Sash windows. We frequently specify oil-based products for sash windows in period London properties. The flexibility, the hard cure, and the self-levelling quality of oil-based eggshell all suit the demands placed on sash window joinery.

High-wear interior joinery. Hallways, staircases, and kitchen joinery that takes heavy daily use benefit from the ultimate hardness of a fully cured oil-based finish.

Radiators. Oil-based finishes handle the heat cycling of radiators better than water-based alternatives, which can yellow or discolour over time with repeated heating.

Where Water-Based Systems Are Better

The modern generation of water-based eggshells, satinwoods, and gloss paints has genuinely closed the gap on oil-based products in most applications. Water-based products win on:

Colour retention and non-yellowing. Oil-based paints yellow with age, particularly in rooms with limited natural light. White oil-based woodwork in a hallway or staircase will visibly yellow over five to ten years. Water-based whites stay white for much longer.

Application in occupied properties. Lower odour, lower VOC, and faster drying means less disruption.

Walls and ceilings. Oil-based products are rarely used on walls and ceilings in domestic properties. Modern water-based emulsions and flat finishes are excellent and there's no meaningful argument for oil-based alternatives here.

Environmental considerations. Water-based systems produce less hazardous waste and the disposal of water-based paints and clean-up water (diluted to trace levels) is far less problematic than solvent-based waste.

The Hybrid Option: Water-Based Alkyds

A relatively recent category worth knowing about is water-based alkyd paints — products that use an alkyd resin (traditionally associated with oil-based paints) dispersed in water. These aim to combine the finish quality, self-levelling, and hardness of oil-based products with the low VOC and faster drying of water-based systems.

Brands like Dulwich Trade Satinwood, Zinsser AllCoat, and some of the Farrow & Ball Modern Eggshell formulations fall into this category. In our experience, they're genuinely good products that suit most situations where you'd have previously specified an oil-based satinwood. They're not quite as hard when cured as a traditional alkyd, but they come close.

Making the Decision for Your Property

In most circumstances for London period properties, our default specification is:

• Water-based emulsion on walls and ceilings throughout
• Water-based eggshell or satinwood on most interior joinery, particularly where the property is occupied
• Oil-based primer on bare timber before any water-based finish coats
• Oil-based eggshell or satinwood on sash windows and high-wear joinery in key areas like hallways
• For exteriors, a silicone or acrylic-modified masonry paint on rendered surfaces

This hybrid approach gives you the best of both systems. It's not dogmatic about either, and it reflects what we've learned through working on hundreds of period London properties over the years.

If you're unsure what's right for your specific project, we're happy to talk through the options during a site visit.