Walk through any newly renovated property in Belsize Park, and the flooring will tell you everything about the homeowner's priorities. Polished concrete speaks to minimalist aspirations. Wide-plank reclaimed timber suggests a farmhouse aesthetic. But in nine out of ten high-end renovations, the choice is consistent: engineered oak laid in herringbone pattern, finished with an invisible oil.

This is not a trend—it is a considered choice based on acoustic performance, compatibility with underfloor heating, longevity, and timeless aesthetic appeal. Here's why herringbone oak remains the definitive flooring for period properties in North West London, and what you need to know when specifying it.

The Case for Engineered Oak

Engineered oak is not a compromise. It is a technical solution that outperforms solid oak in almost every scenario relevant to Hampstead homes.

Construction

An engineered oak board consists of three layers:

1. Top Wear Layer: 4-6mm of solid oak (the species, grade, and finish you select)
2. Core Layer: Typically birch or pine plywood for dimensional stability
3. Backing Layer: A balancing layer that prevents cupping or warping

This construction means engineered boards do not expand and contract with moisture changes to the same degree as solid timber. In a London climate—where relative humidity swings from 40% in winter (due to central heating) to 70% in summer—solid oak will gap between boards in dry conditions and swell in humid conditions. Engineered oak remains stable.

Compatibility with Underfloor Heating

Period properties in Hampstead typically have suspended timber floors. When adding underfloor heating (either hydronic systems beneath a new screed, or electric mat systems), you need a flooring material that conducts heat efficiently and tolerates temperature fluctuations.

Solid Timber: Reacts poorly to underfloor heating. The constant warming and cooling accelerates expansion/contraction cycles, leading to gaps, cupping, and even board cracking.

Engineered Oak: Designed for underfloor heating. The plywood core remains dimensionally stable, while the 4-6mm oak wear layer is thin enough to conduct heat efficiently. Maximum temperature should be limited to 27°C (measured at the floor surface), but within this limit, engineered oak performs flawlessly.

Polished Concrete: Conducts heat excellently but is cold underfoot when heating is off, acoustically harsh, and visually stark. It works in contemporary loft conversions but clashes with period architecture.

Porcelain Tiles: Similar to concrete—excellent heat conduction, but hard, noisy, and visually unsuitable for Victorian or Edwardian interiors.

Acoustic Performance

In a conversion flat or a terraced house with party walls, acoustic performance is critical. Hard flooring transmits impact sound (footsteps, dropped objects) to rooms below and adjacent.

Building Regulations Part E requires impact sound insulation of at least 62dB for conversions. Achieving this with hard flooring requires:

• Acoustic underlay (typically 5mm rubber or foam)
• Proper isolation from walls (expansion gaps with compressible foam strips)
• In some cases, a floating floor construction with resilient cradle systems

Engineered oak on a good acoustic underlay typically achieves 60-65dB impact sound reduction—borderline compliant. Polished concrete without extensive acoustic measures will fail Building Control inspection.

For upper-floor rooms in a house, the same principles apply: timber flooring on acoustic underlay dramatically reduces noise transmission to rooms below. Families with children particularly value this.

The Herringbone Pattern

Herringbone—where boards are laid at 45-degree angles in a repeating zigzag pattern—is more expensive than straight-lay (parallel boards) or chevron (boards cut to 45-degree angles meeting in a point). So why specify it?

Visual Impact

Herringbone draws the eye across the room, creating movement and interest. In a period property with high ceilings and generous proportions, herringbone complements the architecture's formality. It also disguises imperfect room geometry—Victorian walls are rarely perfectly square, and herringbone's diagonal lines are more forgiving than straight boards, which emphasize any deviation.

Historical Authenticity

Herringbone parquet was the prestige flooring choice in Georgian, Victorian, and Edwardian homes. Original examples (often oak or mahogany) survive in grander Hampstead properties, particularly entrance halls and reception rooms. Specifying herringbone in a renovation is not mimicry—it is continuity with the building's original design language.

Longevity of Aesthetic

Straight-lay oak in wide planks (200mm+) was the dominant trend from 2010-2015. It now looks dated. Herringbone has been installed in high-end London homes for 150 years and has never fallen out of favor. It is not a trend; it is a classic.

Selecting Grade: Prime vs. Rustic

Oak flooring is graded based on the presence of knots, color variation, and grain patterns. The two grades that matter for North West London interiors are Prime and Rustic.

Prime Grade (also called Select or Grade A)

• Characteristics: Minimal knots (small, tight knots only), consistent color, straight grain.
• Aesthetic: Clean, refined, elegant. Works in contemporary interiors and period properties where a neutral backdrop is desired.
• Cost: £80-£140 per sqm depending on brand and finish.
• Considerations: Too uniform for some tastes. Can look bland in large open-plan spaces without sufficient natural light contrast.

Rustic Grade (also called Character or Grade B)

• Characteristics: Knots of varying sizes, color variation from pale honey to dark brown, occasional mineral streaks or sap marks.
• Aesthetic: Natural, characterful, warm. Suits period properties where imperfection is celebrated.
• Cost: £60-£100 per sqm.
• Considerations: Some knots may have small voids (filled during manufacture). Not suitable for ultra-minimalist interiors.

The Hampstead Consensus

In practice, most high-end renovations in Belsize Park and Hampstead specify Prime grade with a medium stain or Rustic grade with a light natural oil. Prime grade left natural can look too pale and clinical; Rustic grade with a dark stain can look muddy. The middle ground—Prime grade oak with a Smoked or Grey-Brown oil finish—achieves the most balanced result.

Finish: Invisible Oil vs. Lacquer

The finish protects the oak and defines how it looks and feels underfoot. There are two main categories:

Invisible Oil (also called Natural Oil or Hardwax Oil)

• Appearance: Matte finish. The oak looks unfinished—you see the natural grain, texture, and color without any surface sheen.
• Touch: Slightly textured. The oil soaks into the timber rather than sitting on top.
• Maintenance: Requires re-oiling every 2-3 years (a DIY task). Scratches and marks can be sanded out locally and re-oiled without refinishing the entire floor.
• Brands: Osmo, Rubio Monocoat, Bona.
• Best for: Period properties, family homes where wear will occur and easy repair is valued.

Lacquer (also called Varnish or UV Lacquer)

• Appearance: Satin or gloss sheen. The timber is visibly coated, giving a more polished, formal look.
• Touch: Smooth, hard surface.
• Maintenance: Very low maintenance—can be mopped with standard cleaners. However, scratches cannot be locally repaired; the entire floor must be sanded and re-lacquered (a professional job costing £25-£40 per sqm).
• Best for: Commercial spaces, rental properties, or homes where occupants will not tolerate any maintenance.

The Verdict

For owner-occupied family homes in Hampstead, invisible oil is the correct choice. Lacquered floors look plasticky and wear poorly—any scratch exposes raw wood beneath the coating, creating unsightly white marks. Oiled floors age gracefully, developing a patina that enhances their character. Scratches blend in, and periodic re-oiling (a weekend task) maintains the finish indefinitely.

Brands and Suppliers

Not all engineered oak is equal. The thickness of the wear layer, the quality of the plywood core, and the precision of the tongue-and-groove joints vary significantly.

Premium Brands

Havwoods: British brand with showroom at 250 Finchley Road (Palace Court). Known for exceptional quality, wide range of finishes, and good technical support. Prime grade herringbone in natural oil: £110-£140 per sqm.

Hakwood: Dutch manufacturer, favored by architects. Extremely precise machining, huge color range. Slightly higher cost (£130-£160 per sqm).

Solidfloor: Belgian brand, excellent for custom stains and unusual plank sizes. £100-£130 per sqm.

Kährs: Swedish brand, good mid-range option. Reliable quality, less expensive than Havwoods. £70-£100 per sqm.

Where Not to Buy

Volume Builders' Merchants: Travis Perkins, Jewson, etc., stock engineered oak, but it is typically lower quality with a 3mm wear layer (vs. 4-6mm in premium brands). This matters—if you ever need to sand the floor to remove deep scratches, a 3mm layer can only tolerate one sanding; a 6mm layer can be sanded twice.

Online-Only Suppliers: Unless you can view samples in person, avoid. Oak color and texture vary hugely, and screen images are unreliable. You need to see and feel the boards before committing.

Installation Considerations

Herringbone installation requires skilled labor. A poorly installed floor will gap, creak, or fail underfloor heating commissioning tests.

Subfloor Preparation

The subfloor must be:

• Flat: Deviations of no more than 3mm over 2 meters. Any high spots must be ground down; low spots filled with leveling compound.
• Dry: Moisture content below 75% relative humidity (measured with a hygrometer). Screeds must be fully cured (minimum 1 day per mm of thickness, so a 75mm screed needs 75 days).
• Clean: Free from dust, plaster, or adhesive residue.

If installing over underfloor heating, the system must be commissioned (gradually warmed up over 7-10 days) before flooring installation.

Acoustic Underlay

For upper floors or conversions, specify:

• 5mm Acoustic Rubber Underlay: Standard for most residential applications. Achieves 60-62dB impact sound reduction.
• 10mm High-Performance Underlay: For new-build flats or conversions where Building Control is strict. Achieves 64-66dB reduction but adds £15-£20 per sqm to cost.

Acclimatization

Engineered oak must acclimatize to the room's humidity before installation. Boards should be delivered, unpacked (but left in stacks), and left in the room for 48-72 hours. This allows the moisture content to equalize, preventing expansion or contraction after installation.

The Installation Process

1. Underlay Installation: Rolled out, joints taped, cut around door frames and pipes.
2. First Row: The installer sets out the first row of herringbone along the longest wall, ensuring it is perfectly straight (any deviation will be magnified across the room).
3. Progressive Laying: Each board is glued (tongue-and-groove joint glue, not adhesive to the subfloor) and clicked into place. Herringbone requires cutting each board at a 45-degree angle, so there is more waste (factor 15% extra material) than straight-lay.
4. Expansion Gaps: A 12-15mm gap is left around the perimeter and filled with compressible foam strips. This gap is concealed beneath skirting boards or beading.
5. Finishing: Any surface adhesive is cleaned immediately. The floor must not be walked on for 24 hours.

Cost of Installation

Expect to pay:

• Straight-Lay Engineered Oak: £25-£35 per sqm labor
• Herringbone Engineered Oak: £40-£55 per sqm labor (due to the cutting and precision required)

Total cost (materials + labor) for herringbone oak in a 50 sqm open-plan room:

• Materials (Havwoods Prime grade): £6,500
• Underlay: £500
• Labor: £2,500
• Total: £9,500 (£190 per sqm)

Maintenance and Longevity

Routine Cleaning

• Daily: Sweep or vacuum (use a soft brush attachment, not a beater bar which can scratch).
• Weekly: Damp mop with clean water or a pH-neutral wood floor cleaner. Never use bleach, ammonia, or abrasive cleaners.
• Stains: Wipe immediately. Oil-based stains (cooking oil, grease) are the most problematic—use a degreasing cleaner specifically for oiled wood.

Re-Oiling

Every 2-3 years (depending on traffic), re-oil high-traffic areas:

1. Deep-clean the floor with a wood floor cleaner to remove dirt and old oil residue.
2. Lightly abrade the surface with a buffing pad (not aggressive sanding—just scuffing the surface to allow the new oil to penetrate).
3. Apply a thin coat of hardwax oil with a lint-free cloth or roller.
4. Allow to cure for 12-24 hours.

This is a DIY task that costs £50-£100 in materials and takes a day for a 50 sqm area.

Longevity

A well-maintained engineered oak floor will last 30-50 years. The 4-6mm wear layer can be sanded once or twice if deep scratches or stains develop (though with oiled floors, this is rarely necessary). After 50 years, the floor can be lifted and replaced—unlike polished concrete or stone, which are permanent (and expensive to remove).

Why Not Other Options?

Polished Concrete

Popular in warehouse conversions and ultra-contemporary homes, polished concrete has significant drawbacks:

• Cold: Even with underfloor heating, concrete feels cold when the heating is off.
• Hard: Acoustically harsh, uncomfortable to stand on for long periods, dangerous for young children (falls on concrete cause more injuries than falls on timber).
• Irreversible: Once poured, removing concrete is a major undertaking.
• Aesthetic: Clashes with period architecture. A Victorian terrace with polished concrete feels disjointed.

Wide-Plank Reclaimed Timber

Reclaimed oak, pine, or elm in 200-300mm planks has rustic appeal but several issues:

• Condition Variability: Reclaimed timber comes from demolished buildings. Nail holes, stains, and structural defects are common.
• Dimensional Instability: Old timber has been exposed to decades of moisture cycling. It is more prone to warping and gapping than new engineered boards.
• Limited Availability: Finding enough reclaimed boards of consistent species, width, and condition for a large project is difficult and expensive.

Luxury Vinyl Tile (LVT)

LVT mimics the appearance of wood or stone but is plastic. It is cheap (£30-£50 per sqm installed), waterproof, and low-maintenance—but it is not appropriate for high-end homes:

• Appearance: Even premium LVT looks like a photograph of wood, not actual wood. The grain pattern repeats, and there is no texture.
• Longevity: 10-15 years before it wears out and must be replaced. Engineered oak lasts three times longer.
• Resale Impact: Buyers expect real materials in properties above £1.5m. LVT signals cost-cutting.

Conclusion

The choice of flooring is not merely functional—it defines how a space feels, how it sounds, and how it will age. In the context of Hampstead and Belsize Park, where period architecture, underfloor heating, and acoustic considerations intersect, engineered oak in herringbone pattern emerges as the optimal solution.

It is not the cheapest option, but it is the most considered. It respects the architecture, performs technically, and will still be beautiful in thirty years. For homeowners who view their property as a long-term investment rather than a short-term asset, herringbone oak is not a trend to be followed—it is a decision to be validated by time.

To see these textures in person, we recommend visiting the material library at Palace Court (250 Finchley Road), where large-format samples from Havwoods, Hakwood, and other premium brands are available to view. Observing how different grades and finishes respond to natural light is essential before specification.