It sounds like the perfect way to buy a holiday home at low cost — purchase a share in a Devon cottage, yours to use or rent out for a quarter of the year while you pay someone else to mow the lawn and fix the occasional cracked windowpane. But does this method of buying a part-stake in a home, known as fractional ownership, really work in Britain?

Under the system, well-established in America, buyers purchase a stake in a property allowing use for a set number of weeks per year. Unlike timeshares, fractional ownership’s much — and often rightly — maligned cousin, buyers also receive a share of the leasehold or freehold, allowing them to benefit from capital gains.

Philippa Hughes, owner of 400-acre Holwell Farm near Widecombe-in-the-Moor, Devon, is one of Britain’s fractional pioneers. She is selling 24 “quarters” of six cottages, each with three or five bedrooms, for £130,000 to £165,000 per slice, plus a £2,800 annual service charge.

Each “quarter” entitles the buyer to 12 weeks’ use, divided into six blocks; to ensure fairness, the rota moves forward by a week per year, although owners are free to swap time with each other. The cottages are managed; owners enjoy fresh laundry plus a stocked fridge at the start of their stay.

“Dartmoor is an all-year location for walkers or explorers, and the cottages have the bonus of being on a working farm — that’s a year-round experience,” says Hughes.

But there are potential drawbacks behind Holwell and the other 20 or so fractional schemes on offer in Britain.

“You can’t get a mortgage easily on a fractional property because lenders aren’t confident there’s a resale market yet, and they don’t know if the concept will take off,” warns Chris Tanner, managing director of Blevins Franks, a financial advisory service. “So a buyer will probably have to pull down equity from their main house. They could use that sum instead as a deposit on a buy-to-let or on a holiday cottage. They could let out either of these in the usual way and not have to share the rent and capital uplift with other buyers.”

Buyers may also find they are sometimes paying over the odds for the property. Jackson-Stops & Staff estate agency is selling a four-bedroom house at nearby Chagford with what it calls “spectacular Dartmoor views” for £385,000 — well under the £520,000 that “four quarters” of the fractional ownership cottage would cost.

Local lettings agents say owners in this area could enjoy a maximum 16-week rental season if they let out a cottage over the entire summer, when good weather is likely. That makes only four weeks, though, for each fractional owner to make money through renting out their quarter share. During the rest of the year, there are relatively few potential renters in the southwest.

Indeed, the weather is the biggest question mark over the concept, which began in the 1980s in Florida and other popular holiday home areas of America, before spreading to resorts in South Africa, the Caribbean and southern Europe. Two factors common to these locations, but absent in Britain, are year-round good weather, and a tradition of year-round rentals.

“Fractional ownership is only for warm locations,” says Andrea Lee, sales manager of Poole-based Select Resorts, which sells homes overseas, including one fractional ownership golf course scheme in the Algarve. “It doesn’t matter there if your allocation is winter or summer because it’s warm all year and golfers will rent in December or August.”

Christian Jensen-Broby, a spokesman for Marriott, the American hotel chain behind fractional schemes in Florida and other sun-kissed locations around the world, agrees: “We wouldn’t run fractional ownership in the UK outside of London. There’s a reason we haven’t opened any resort-style fractionals in this country. It’s called the rain.”

Marriott’s only scheme in Britain is 47 Park Street, a chintz-and-Chesterfields block of flats in Mayfair, close to Hyde Park. Three-week fractions, with leases expiring in 2050, cost from £106,000 for a small one-bed flat up to £180,000 for a larger two-bed unit, and annual service charges averaging £5,100.

But is that such a bargain? A fractional one-bed unit at 47 Park Street would cost more than £1.5m if you bought up all its weeks; you should be able to buy a small flat in Mayfair outright for £550,000. The company insists their units boast a series of luxury features, including maids and 24-hour concierge service.

Take-up of such schemes in Britain has been slow. Marriott admits it has sold only 60% of 47 Park Lane’s 637 slices after six years on the market; fewer than a third of these have gone to Britons — Americans and Asians are the main customers.

Things are not going much better in the southwest. Penhaven Cottages, a north Devon scheme of 10 homes, each split into 10 fractions of five weeks costing £19,500 to £31,000 with up to £1,600 service charges, has been on sale since last summer — more than half are still available.

Holwell Farm is back on the market through two top-end estate agencies after a break of over a year. So far, no sales have been completed, although Hughes says eight “quarters” are due to exchange at the end of this week, with two more due next month.

- Holwell Farm is for sale with Knight Frank, 01392 848 848, www.knightfrank.comand Jackson-Stops & Staff, 01392 214 222, www.jackson-stops.co.uk; Marriott 47 Park Street, 020 7950 5528, www.47parkstreet.com; Penhaven Cottages, 01237 452 143, www.penhavencottages.co.uk

Times recommends

• Fall in house sales hits builders, estate agents and mortgage brokers
• Why the property credit crunch favours cash buyers
• The blood-curdling history of Quarrelwood House