This entails a round trip of over 1,000 miles driving and around 10,000 ft of climbing - the equivalent of about one third of the height of Mount Everest.
The team will include six climbers with a support team of three, travelling in a 17 seat minibus on loan from the Gloucester Rugby Community Team.
Brunsdon Partner Neville Mills, who is co-ordinating the event, said: "It is quite a tough event to take on in just 24 hours but, although none of us is an experienced mountaineer, we are fairly confident we can manage it and obviously we have been doing some training to get fit.
"We are all looking forward to it as we will be travelling through some of the most stunning scenery in all three countries, providing the visibility remains clear.
"We are hoping to raise £5,000 for the Pied Piper Appeal children's charity as part of the £15,000 total Brunsdon has committed to raise. The money will help refurbish the Children's Centre at Gloucester Royal Hospital, which Pied Piper helped to establish in the first place.
"This event requires some fairly detailed planning to make sure we don't get tangled up in the rush hour around big cities like Glasgow and Manchester and of course we need to have as much of the climbing as possible done during the hours of daylight.
"We will start at Fort William at around 5pm and then drive through the night to arrive at Scafell near first light, moving on to Snowden by lunchtime.
"The summit plateau of Ben Nevis can be particularly treacherous in poor visibility as there are sheer 2,300 ft cliffs falling away on one side and the weather can come down with very little warning at any time of year.
"We are already collecting the maps, compasses, head torches, wet weather gear, boots and other specialist clothing and equipment we shall need for the trip.
The climbers are Neville Mills, Rob Minshull, Kevin House, Howard Beddoe, Kevin Parkhouse, all from Brunsdon, and 'guest' Gary Little, Community Manager for Gloucester Rugby Club. The support team consists of Paul Baldwin, Steve Tasker and Dave Morman.
Gary Little, Gloucester Community Manager, said:
'Brunsdon are long standing corporate partners and box holders at Kingsholm. Its great to be involved in the challenge and to be invited to help them in raising funds for one of the clubs chosen charities Pied Piper.'
The Brunsdon team are no strangers to adventurous fund-raising exploits. In 2007 Brian Morman, Managing Partner, and his brother, David, Marketing Manager, rode the 2,600 miles from Chicago to Los Angeles along the route of the Legendary Route 66 on Harley Davidson motorcycles to raise money for the National Star College in Cheltenham.
http://www.justgiving.com/brunsdonheartfeltthreepeaks
For more information call Brunsdon on 01452 623623 or visit www.brunsdon.co.uk Brunsdon LLP, Brunsdon Financial Services Ltd and Brunsdon Insurance Brokers Ltd are authorized and regulated by the Financial Services Authority.
