Keratin & Hair Straightening in Bristol, Bath, Devon and Cornwall: Why the South West Is Two Different Hair Problems

Short answer: The South West is really two regions for hair:

• Bristol, Bath, Somerset, Wiltshire: hard to very hard limestone water. Your hair’s problem is mineral build-up.
• Devon and Cornwall: mostly soft moorland water, but the wettest, windiest weather in England. Your hair’s problem is humidity.

Same treatment names, different reasons they fade. Tell your hairdresser which half you live in.

I’m Zoltan, texture specialist on Maddox Street, Mayfair, perming since 1991 and straightening since 1999. Here’s how I’d think about South West hair.

Bristol, Bath and Somerset: the hard-water half

Bristol Water describes its supply as “moderately hard to very hard”, because the water comes through limestone. Wessex Water’s Bath zone is classed very hard. The Drinking Water Inspectorate calls anything over 300 mg/l very hard.

What the science says, honestly: it’s mixed. One study found hard water didn’t weaken hair over 30 days. Another found more mineral sitting on the hair surface. From the chair, hard-water hair feels rough, tangles, dulls, and makes smoothing treatments seem to give up early.

My advice: clarify every couple of weeks. And if you’re paying for a smoothing, go demi-permanent rather than light. A light smoothing in very hard water can feel like it’s gone in weeks.

Rain here is moderate: Filton (Bristol) 819 mm / 136 rain days, Bath 830 mm / 133 days, Yeovilton 730 mm / 126 days.

Devon and Cornwall: the humid half

South West Water says most of Devon and Cornwall is soft or moderately soft (0–100 mg/l), from moorland reservoirs. East Devon’s borehole water is harder. Soft water is kind to hair and shampoo.

The weather isn’t. Plymouth gets 1,038 mm over 149 rain days. Camborne gets 1,076 mm over 155 days, with average wind of 10.5 knots. Humid air gets into hair’s hydrogen bonds and pulls it back towards curl and frizz. Salt spray on top doesn’t help.

My advice: if you’ve tried smoothing and the humidity still wins, you may want a treatment that changes the hair (demi or permanent) rather than one that coats it.

Which treatment

• Frizz, keep your shape → Straightment Semi, back after 1–4 months (sooner in very hard water).
• The “keratin / Brazilian” result: less curl, much less frizz → Straightment Demi. About 60% of the curl out, roots after 4–8 months.
• Straight (the “Japanese straightening” family) → Straightment Permanent. 80%+ out on the treated hair, for good. Roots after 6–18 months.

Straight talk: If you surf or sea-swim every week, no smoothing treatment will last the way the salon promised. Budget for that, or choose something that isn’t meant to wash out.

More straight talk → The Brief

Finding a salon locally

Bristol, Bath and Exeter all have good salons. Check they:

1. Name the product and its active ingredient.
2. Strand test coloured, bleached, relaxed or previously straightened hair.
3. Ask your full history, including box dye and henna.
4. Never overlap permanent straightener onto already-treated hair.

If you come to Mayfair

Fastest trains to London: Bath 1h13, Bristol 1h19, Salisbury 1h20, Taunton 1h38, Bournemouth 1h45, Exeter 2h00, Plymouth 2h52, Penzance 4h57. Maddox Street is a short walk from Oxford Circus and Bond Street.

From Cornwall that’s a full day, so do the £9.95 online consultation first. You’ll know if the trip’s worth it before you book the train. Permanent straightening only needs roots every 6–18 months, which suits people who live far away.

Prices: Semi £149.95–£269.95; Demi all-over starts at £199.95; Permanent all-over starts at £299.95.

— Zoltan

Sources

• Bristol Water — hardness; Bath (WaterGrade, Wessex Water data); South West Water hardness factsheet
• Met Office 1991–2020: Filton, Bath, Yeovilton, Plymouth, Camborne
• DWI — hardness bands; Srinivasan 2013; IJDVL
• GWR — London to Bristol; Trainline — London to Penzance (and equivalents)