Thrifty Homes to Save the Planet: Renewing Old Homes for a Green Future

Nick Cragg of Cragg Management Services is one of the experts helping to fulfil our vision. He talked us through the measures needed to turn just one of our properties, the 100-year-old 2 Brinkhill Bridge Cottage, into an efficient and desirable 21^st-century home.

“2 Brinkhill Bridge Cottage isn’t listed but it has heritage,” said Nick. “We were keen to maintain its feel and nature. Typically for its time, it was built with a single, solid wall with no cavity. In the late 20^th-century, an interior insulation layer of polystyrene-backed plasterboard was fitted.

“Properties of this era had a single-skinned wall finished with a lime and plaster render. Solid walls weren’t designed with insulation or centrally heated temperatures in mind. They were designed to breathe, with moisture condensing on the exterior of the wall. The effect of bad, retrofitted insulation can be to stop the walls breathing, and to bring condensed moisture into the structure where it builds up in the plaster and mortar.

“We stripped off the old lining and added 40mm of wood-walled insulation board with a lime render. We could have scored higher on the EPC (Energy Performance Certificate) with a 70mm board, but this would have prevented the building from breathing and caused humidity problems.

“Next, we tackled the floor. The ground-floor was a concrete slab laid on earth with no insulation at all. We broke up and dug out the whole slab, then excavated down and put in an insulated concrete slab with a 300mm layer beneath. This will prevent cold coming in from below, and heat sinking downwards.

“We then insulated the roof space, including the gaps between rafters. Overall, we created an insulated box while avoiding damage to the building’s key features. All the single-glazed windows were replaced with matching wooden-framed, double-glazed units. Existing doors were proved, made good and draught-proofed.

“The oil-fired boiler was taken away and replaced with a ground-source heat pump. This system uses pipes sunk into a 70m borehole in the garden. Essentially, the ground itself provides the energy for heating and hot water. Ground-source can cost up to ten-times more than a boiler, but it’s clean, sustainable and consumes negligible energy.

“Underfloor heating was installed on the ground floor as it’s far more efficient than wall-mounted radiators. We fitted new sanitary ware, including water-efficient taps and WCs. Rainwater harvesting was unfortunately not viable given the size of the property, but water-butts will be used outside. We capped the old cesspit – cesspits are being phased out – and replaced it with a domestic sewage-treatment plant, which takes in waste and produces clean water. The property will be finished off with a charge-point for electric cars and, as a welcome mat for wildlife, bat boxes.

“2 Brinkhill Bridge Cottage may well have been the estate’s oldest and trickiest property for this sort of project. It’s a microcosm of the estate’s aspirational approach; a proving ground and an investment in learning what’s possible when it comes to making property sustainable.

“Some landlords put their heads in the sand when it comes to bringing rental properties up to current and future efficiency standards. Jon Thornes is getting well ahead of the game, and first and foremost wants South Ormsby Estate to be an ecological exemplar for the whole world.”

The EPC is a key aspect of central government’s effort to drive down carbon emissions. Anyone buying, selling or renting a property must have one, and failure to meet efficiency standards can have consequences. South Ormsby Estate aims to take its older, F-rated properties and upgrade them to ‘C’ or ‘B’ ratings.

Tony Cranwell of Horncastle-based Links2Lincs is an experienced energy assessor and gave us some insights into the ins and outs of EPC ratings, as well as some tips on how landlords and residents can make their homes warm and energy-efficient.

“I initially carry out free energy audits for people thinking about improvements,” said Tony. “I give them guidance on how to get the best outcome with a view to returning at the end of the process and getting a better result.

“Rental properties need a minimum level of efficiency by law, failing which landlords can be fined. Any property not assessed at ‘E’ or above after November 2020 will attract local authority fines. I’ve been getting phone calls from landlords who’ve been given six weeks to sort out their rating. Typically, they just want the minimum investment to get to ‘E’, but it’s interesting that the government is considering leapfrogging ‘D’ and changing the minimum standard to ‘C’. The government’s ultimate goal is zero carbon emissions by 2050 and that’s the real reason for the EPC; not to save the occupier or the landlord money.

“An EPC assessment takes about 45 minutes in an empty property. It’s based on the volume of space we want to heat, how that heat is generated and how the heat is kept in. I’ll look at the lighting, the levels of insulation in the floors, walls, windows and loft, and the efficiency of the means of heating water and radiators.

“The EPC is based on a 100-point scale, starting with a ‘G’ rating at 1 point and ending with an ‘A’ rating at 100 points. Expensive improvements aren’t always the best for improving a rating. Householders should look carefully at basic loft insulation as that can be worth 40 points. Efficient, mains heating can also be worth 40 points. An unblocked flue can cost 2-3 points, while blocking it with a decorative LPG fire can add 8 points. Replacing double-glazing might only get you 1 point, but  whether you’re a resident or a landlord, I’d always advise keeping on top of draught-proofing.

“It’s absolutely vital to get an expert opinion before you commit to big improvements. A bodged, remedial insulation job can make things worse and cost EPC points. Cavity wall insulation, for example, can introduce damp in a property not designed for it.

“Jon’s plan is the most ambitious I’ve come across and South Ormsby Estate is very proactive about energy efficiency. There is more movement across the region to improve energy efficiency, but this only got going in the last six months and mostly because of the minimum ‘E’ rating. Landlords need to think further ahead as minimum standards will be rising.

“Jon Thornes clearly wants more than the minimum. He wants to get the best possible outcome despite the challenge presented by the age of some of the properties and the lack of mains gas. A lot of landlords tinker around the edges, but South Ormsby is really going for it.”

Slashing carbon emissions across the estate to mitigate climate change, while creating desirable and energy-efficient homes fit for future generations, is a vision we intend to turn into reality across South Ormsby Estate. If the lessons we learn in the process can inspire others across the region and beyond, then the benefits will be truly significant.