Building a Rental Holiday Home

[Mugwanya]

Hi All

 

Attached are the plans for the homes that I have permission for; I plan to change the three bedroom one so that the rectangle is completed (which would allow for en-suites to the relevant bedrooms) and also to have a flat sloping roof at an angle of between 20 and 35 degrees (dependent on what the planners will allow) so that the whole roof is available for solar panels. 

The structure will use SIP panels with a U value no more than 0.13, a SIP roof, triple-glazed windows (Munster Joinery seem good but I haven't obtained quotes yet) and insulated foundations. So not aiming for Passivhus on my first build but I want to try to get close-ish.

I'm looking for MVHR for a bit under 200m2 of floor area (but bear in mind the high ceilings on the first floor). I'd like comfort cooling for the hopefully hot summers to come. Water heating needs to support three showers/sinks in the en-suites, sink and bath in the bathroom and sink in the kitchen. I'm not planning underfloor heating but infra-red radiant but that is under review.

The property will have no gas and probably no grid electric, so lots of solar panels and big batteries. So the plan was to have an Ariston Nuos cylinder with built-in heat pump, immersion and 200l (or 250l) of water storage plus a 300l indirect cylinder with an immersion. So the Nuos could be used to heat the water in the second cylinder and in itself using its heat pump, but the immersions could be used if needed. But I'm also talking to Total Home about their systems (PKOM4, Joule and heat pump MVHRs) because they look interesting.

I'm working on the basis that these are holiday homes, so likely to have gaps between bookings. So the hope is that a lot of the time the batteries will be full and the solar energy can be used to just heat up the water. And I want to cater for the booking that has 6 adults, 5 of whom have showers in the morning and one has a bath. So lots of hot water needed, hence the two cylinders.

The house will also need a sewage treatment plant; I'm currently favouring the new Solido over the Vortex or the Graf though I don't know enough to justify my choice; I think they'll all do the job and in the end I just had to pick one. Would have liked to have had the choice of one of the non-electric plants but they seem to be about £2,000 more than the electric and I don't believe the savings are worth it.

 

Anyway, nice to be here listening to you all

 

Derek Mugwanya

A.02_First_Floor_Plans_and_Elevations.pdf A.05 First Floor Plans and Elevations.pdf

[PeterW]

So first observation would be that batteries and rentals don't mix.. people renting holiday homes don't switch lights off, and if you give them aircon too then they will use it. If you're going down that route then you will need very deep pockets as the power usage on aircon and the batteries needed will be eye watering.

 

 

[Mugwanya]

I'm not planning to give them air con, just comfort cooling in the summer. Maybe knock 4 degrees off outside ambient. 

I've been quoted 23 grand to get electric to the site. That buys a lot of battery. Now 14 of  to go elsewhere to get it done cheaper, running the lines 25 metres down the road, so I might end up being able to do that. But I'm attracted to being completely off grid, batteries plus a generator.

[PeterW]

£23k won’t buy you a lot of batteries - a single Tesla Powerwall installed is £7k, you’ll need 6 in reality to give you anywhere close to the storage you need with 2 per unit. 

Thats £42k of batteries, plus a backup generator for around £6k with all the toys, and then solar on top will be another £15k if you factor in the installs etc. 

That is £63k to be self sufficient - I would anticipate that those units will use £3-400 of electricity each per annum, so your payback on this is around 33 years .... 
 

Are you building these as a business as you can’t reclaim VAT on holiday homes as a self builder ..?

 

 

[Mugwanya]

So I guess it won't be cost effective. I'm planning to build just the three bedroomed house this year, and had hoped to put in 17KWh of Solax batteries, or the Pylontechs, which list at under 7k, and the comfort cooling adds maybe 3k to the cost of the MHVR, either by adding a heat pump or an evaporator.

 

You're saying I'll need twice as much battery storage?

 

I am building as a business and am aware of the VAT implications. Thank you for your input, particularly if it stops me going in the wrong - expensive- direction. I will pursue quotes to get a trench dug.

[Jeremy Harris]

The challenge with getting a house to work easily off-grid is that power generation from PV won't come close to being enough during the time of year when electricity is most needed, so alternative sources, like wind or hydro need to be added, unless the house is to be reliant on a generator from around October to March each year.  Storage doesn't help much, as the fundamental problem is that there just isn't enough power available for excess to be stored at times.  If installing a generator then it's cheaper to run that to power things directly than to try and store power in a battery pack, because of the losses incurred when both charging and discharging the batteries.

 

We have a fairly large PV array, 6.25 kWp, and our 130m² house only needs a small amount of heating, which is all electric (with a heat pump).  The PV contributes nothing at all to the heating in winter, just because we can go for days with very little generation.  This graph of the typical output for our PV system across the year illustrates the problem, lots of generation in summer, when we don't really need it, and very little in winter when we do:

 

[Mr Punter]

I am afraid the £23k is the way forward.

 

Hopefully you have mains water?

[Mugwanya]

I have a friend with an array close to where my plot is and from his figures for last winter I'd worked out that a 10KW array would see me through most of the winter with the odd bad week on the generator. Also as a holiday home the winter is likely to be the least busy time; if it is a week between lets then it does become an issue of storage.

 

But I accept the advice that on grid is the way to go and will look at reducing the cost of getting the supply to the site.

 

Thanks

 

Derek

[Mugwanya]

I will have mains water. The water company have been extremely helpful; I just need to install three standpipes and they will put in supplies for all three houses, even though two of them won't be started for a couple of years. I've built the standpipes but need to build secure housing so I've got to ask them if I can do one housing for all three or if they need to be individual.

[Jeremy Harris]

11 minutes ago, Mugwanya said:

I have a friend with an array close to where my plot is and from his figures for last winter I'd worked out that a 10KW array would see me through most of the winter with the odd bad week on the generator. Also as a holiday home the winter is likely to be the least busy time; if it is a week between lets then it does become an issue of storage.

 

But I accept the advice that on grid is the way to go and will look at reducing the cost of getting the supply to the site.

 

Thanks

 

Derek

 

 

Easy enough to see how much you might generate using the PVGIS online tool: https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html#PVP

 

It's pretty accurate in my experience; the prediction for us is within a few percent of our actual generation. 

[Mugwanya]

The other consideration was to use something like a Sunamp thermal store, again with the aim of using the unoccupied days' sunshine to prepare for dull but occupied days. That also means a large-ish initial outlay - over £2k for the equivalent storage of a £500 cylinder, but the heat is retained for a lot longer so there is a trade-off. My thought was that two UniQ 12s could store 2 or 3 day's worth of hot water. But I'm looking into how long they can store the heat.

[Jeremy Harris]

We have a Sunamp UniQ 9, and it loses around 740 Wh/day, so over 3 days it would lose about 2.22 kWh.  The 12 kWh version loses about 810 Wh/day, so would lose about 2.43 kWh over 3 days.  The temperature of the initial hot water after 3 days will be pretty much the same as it would be a few hours after charging, as they don't cool down the way a hot water cylinder does, as the heat is stored as a consequence of the phase change of the material inside the thermal battery, very much like a sodium acetate hand warming pad.

[SteamyTea]

Hello.

Are you in the UK? or elsewhere.

 

have you considered bottled gas or a larger cylinder?

 

I worked out that to run my house from batteries for 3 days would cost over £60,000, but that was 15 years ago (when deep discharge, lead acid, batteries where king).

[Mugwanya]

I'm in the UK, in Derbyshire. If I can't get grid power in at a reasonable price now then an option would be to not rent it out for 3-4 winter months, with the intention of using next year's rental income to pay for the grid connection. That may not be so bad, as at the moment with Covid I don't think it will be finished until next year anyway, and if it was no one will be allowed to book holidays.

 

So 10kWh of panels, 17kWh of battery, two 9 or 12 Sunamps fed from a Nuos heat pump and make sure that the solar inverter has a grid connection for later. Then no rentals until next spring/summer.

[Mugwanya]

And I'm talking to a company about doing the installation of the renewable stuff, I'm half hoping they'll say that it is overkill and reduce the number of panels, batteries and maybe one of the Sunamps.

[Mike]

You could also look at limiting the opportunity for energy use - all-LED lighting, microwave oven (only) instead of traditional oven, scrap any baths and have only a shower, improve thermal insulation to PassivHaus levels...

[scottishjohn]

suck it up-- get grid power and yes water board will want to supply them all individually 

.think about this carefully --if you never going to sell them or just sell them all to one person ,then can you have one supply,make it a bigger one , to your ground and you split it .

BUT if you ever want to split+sell  them --then you need to have 3 supplies

Edited April 1, 2020 by scottishjohn

[Mugwanya]

Yes, it will be three water supplies and I've built three standpipes. The question is can I put the 3 pipes in one housing or do I need separate housings. 

Paying 23 grand for the grid supply kills my budget, which either means comprimises elsewhere or I put the grid supply in later as the money becomes available. I think that the solar plus batteries plus a generator will suffice for the summer season, so the plan is to get the grid in next October. Unless alternative suppliers can reduce the cost of the contestable works.

[Mugwanya]

@Mike

Yes, I can limit the scope for energy usage. LED lighting was already in the plan, induction hob which used less electricity. But there is a limit how far I can go down that route. People renting a property, potentially for up to two weeks, are going to expect an oven and washer/dryer. I might get away with no dish washer, and all appliances will be as eco as possible. I will consider the bath issue as one wasn't on my original plan, but again the company who will be renting them out for me were quite keen on one; the argument was that guests coming in with muddy dogs or young children will want a bath, so the revised plan has a bathroom with bath just off the entrance lobby so that dogs/kids can be herded straight in.

[scottishjohn]

37 minutes ago, Mugwanya said:

solar plus batteries plus a generator will suffice for the summer season,

what summer season --thats gone for this year 

going off grid will be worst mistake you make --

 but hey you asked for others views ---

[Mugwanya]

Next summer season, I see no way that it is going to be finished this year. Only the ground works have been started do far.

 

And I have accepted, and appreciate, the views that I need to go on grid, the only thing I'm looking at is if I can do it next autumn (2021) rather than straight away if it is going to cost 23k, plus talking to independent companies to see if I can get it down to nearer 10k, which is in my budget.

[SteamyTea]

I don't think you will go off grid for £23k.

And just think how good the reviews will be when your first guests say they could only bath half the dogs and supper was cold.

 

Reliable water, sewage and electricity are a must for a business.

[Russell griffiths]

Totally off topic @Mugwanya but anyway, I would be very careful with regards letting agents and holiday properties 

we own two holiday letts and my wife handles the books for a few others, ours are ok but we have noticed that in times like now when people are cancelling holidays that the letting agents are still taking their commission even though the holiday doesn’t go ahead. 

Look into a contract very carefully. 

 

Ps, if you let someone wash their dog in the bathroom you will need to refurb them every year and extra cleaning every week, warm tap outside for dogs, showers inside for kids, no bath takes too much hot water. 

We allow dogs and charge an additional rate for extra cleaning. 

[SteamyTea]

4 minutes ago, Russell griffiths said:

We allow dogs and charge an additional rate for extra cleaning. 

I have a serous allergy to dogs.  While looking for a holiday rental earlier in the year, I had to discount the vast majority of them.

 

 

[Ferdinand]

On holiday lets, I suggest this forum and videos over at Property Tribes as a good resource.

 

https://www.propertytribes.com/forumdisplay.php?fid=25&action=latest_posts

https://www.propertytribes.com/videos/25/latest

 

And in particular this "top tips" post that covers a lot of ground:

https://www.propertytribes.com/holiday-let-every-portfolio-should-have-one-t-127628186.html

 

These are all by Vanessa Warwick, who is excellent.

 

F