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I'm not writing this to explain the best way to build a large timber garden building -- after all, I'd never built one before either. Rather, I'm hoping that other people will be able to learn from my mistakes, which were prolific. It's also worth bearing in mind that my design accomodates some odd features of our house and garden. In particular, the ground has a pronounced slope -- about 6'' vertically for every 6' in length. This is because our garden is, in effect, on the edge of a railway embankment. There's an almost unlimited amount of soil and gravel above the back of the garden waiting to slide down if I try to level it out, so I've generally felt that it's better to live with the slope than to try to fix it.
The other limiting factor that I have, and most people do not, is a very restricted access to the garden from the road. All building materials have to be carried through the house, negotiating a narrow passageway between two rooms. So there would be no prospect of bringing in a cement mixer, for example, let alone a prefabricated building. The only way to have a substantial garden building was to build it myself from timbers and sheet materials.
Why build a garden office?
It is very unlikely that building a garden shed yourself, from the kinds of materials you can buy from a timber merchant, will be cheaper than buying a standard prefabricated shed from a specialist supplier, even if you don't cost your own labour, which will be considerable. Although many commercial sheds are flimsy, you can get sturdy ones if you're prepared to pay a premium.Although you won't save much money, if any, by building a shed yourself, building a garden office is a rather different matter. Commercial garden offices are designed for all-year-round occupancy, which means that they need a high standard of weatherproofing. It is necessary to include double-skin walls with insulation, pay close attention to waterproofing and damp penetration, and install double-glazed windows. Because the office may house expensive equipment (computers, etc.) security is an issue. In addition, unlike a shed, a garden office needs to have an inviting interior -- no rough-sawn timbers or chipboard floors.
This is why a 16'x8' prefabricated shed or summerhouse can be had for £1500-£2000, but for a prefabricated garden office of the same size, prices start at about £10000 and go upwards from there.
Now, weatherproofing, insulation, and security are partly a matter of choice of constructional materials, but they are also related to design, and constructional standard, both of which are areas where a bespoke construction can score over a prefabricated building.
In short, one of my design goals was to build a garden office for not much more than the cost of a prefabricated shed of similar constructional specification -- about £2000. This turned out to be almost possible, giving a considerable saving over a commercial garden office, even costing my time.
Regardless of the cost saving, if any, an important advantage of building a large shed or garden office yourself, apart from the fact that it gives you healthy exercise outdoors, is that you can have exactly the design you want. In my case, I knew that the building would be bordered by garden fences on three sides, so there was no purpose in having windows or doors in those sides. I wanted plenty of door and opening window area for good summer ventilation, but insulation and double glazing for winter use. I wanted the door to line up with the garden path, so I could get into the building without first walking across the wet squelchy lawn. I also wanted something that looked a bit different from the usual prefabricated shed, and I got that. Whether it looks better or worse is, of course, a matter of opinion, but it's certainly different.
Design and planning
My first design criterion was that the garden office would occupy most or all of the whole width of the garden, and be as large as I could have it without involving the local Planning or Building Control departments. Under current UK legislation, planning approval is generally not required for a garden building that is less than 3m tall at the highest point, and more than 5m from a dwelling and 20m from a highway. But I discussed it with the neighbours before starting work because, apart from the planning issue, I didn't want to upset them.I decided to make the base 16'x8' (or, more precisely 2440mmx1220mm), with a 16'x4' deck to the front, so I could use standard-sized materials with the minimum of cutting. Cutting is straightforward with the appropriate tools, of course, but measuring for cutting is time consuming. I could have made the front-to-back length greater than 8', but the next standard size up would have been 12', and that's just too big for my small garden. In any case, under UK law an outbuilding must comply with certain Building Regulations if it occupies an area greater than 15 m2 and is within 1m of the boundary. Presumably this is to reduce the risk of fire spreading between properties. Since my building is clearly within 1m of the boundary, I wouldn't have wanted to make it so big as to require the additional expense and hassle of Building Regulations compliance. With the roof overhang, the area of my building is 14.4 m2.
My next criterion was that the roof should have a single slope from front to back. This was for simplicity of construction, as well as alleviating the necessity to deal with drainage of rainwater from more than one end of the building. The roof had to overhang by at least 18'' at the front so that the doors and windows could be opened when it was raining.
I wanted to make the roof pitch at least 1:4 so I could use a single layer of roofing felt, and this turned out to be just about possible, while still having the roof joists high enough to clear my head (6'4'') at the low end. The highest I could have the front of the roof was 3m above ground (planning restriction), and the lowest I could have the back was 2.3m (my height plus the thickness of the joist and roofing material, plus a nominal floor height of 300mm), which -- allowing for an 18'' overhang at the front -- gives a roof pitch of 1:4 exactly.
I did toy with the idea of having a curved roof (like the garden offices made by Henley) because I thought it would look nicer, but I suspected that this would be difficult to achieve with timber (Henley's products have prefabricated plastic roofs). In any case, it has turned out to be impossible to see the roof (except from below) from any part of the house or garden.
Foundation
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| The foundation, skids, and bearers |
The other problem is that as there is limited access to the garden, and none from the road, I would have had to mix several tons of concrete by hand. Now, I don't mind hard work, but that's just too much.
So in the end I built the foundation in the form of 15 supports, in three rows of five. Each support conists of a hole about 2'6'' across filled with compacted hardcore and gravel, with between one and four concrete blocks standing on it. The number of blocks reflects the height of the land -- one block at the back left of the site where the ground is highest, four at the front right where it is lowest. As can (sort of) be seen from the photo, I've concreted all around the piles of blocks on each support, so that each support is, in effect, a single lump of concrete 2-3 feet across and 2-8 inches high. Cost of this part of project:
Concrete blocks £100
Approx. one ton of sand, cement, and gravel £100
----
£200
Base, floor, and deck
The concrete supports are spanned by 8''x2'' skids, on top of which are 4''x2'' bearers at 12'' spacing. The bearers are screwed to the skids using steel L-brackets, and at the front another run of 4''x2'' timber is screwed to the bearers using 6'' coach screws. I adopted this arrangement at the front of the base because the weight on the front edge of the base is going to be enormous -- it will support most of the weight of the overhanging roof, and the solid wood doors and windows, and the substantial front cladding. So my hope is that this arrangement will spread the load across the supports more evenly.
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| The main part of the base built and treated with wood preserver |
The building floor is made from four 8'x4' 19mm plywood panels. Note that the panels span the middle of the base, because the front load-spreading timbers can not (they aren't long enough). There's an expansion gap of about 3mm between the panels.
I suggest that it's necessary to be quite careful about the selection and preparation of the timber for the base. Not only will it be in a relatively damp location, but once the structure is built it will be inaccessible for repairs. I think it is important to ensure that no part of the timber is in direct contact with soil, and that you've done everything possible to treat the timber against rot, woodworm, etc. All the base timbers in my building are pressure-treated, and have had at least two subsequent coats of thick, waxy wood preserver. The problem with wax-based wood preservers is that they take weeks to dry in damp, cold weather, but I think it's worth the inconvenience. All the timbers were stood overnight with their ends in buckets of wood preserver, as I think it is the grain ends that are most susceptible to the entry of moisture. There's a vapour membrane between the base and the ground, to limit condensation of groundwater on the bottoms of the timbers. However, I think it's important to keep the vapour barrier as far as possible off the timbers themeslves, as they need ventilation to remove any condensation that does form.
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| The base with front deck under construction |
Using top-quality exterior grade timber, and the 40 litres or so of expensive wood preserver it took to treat them, probably added about £150 to the total cost of the job, compared to using ordinary sawn softwood and a couple of coats of cheap creosote substitute. The deck at the front of the building serves as the step up to the door (which would otherwise be a 12'' step, the ground slope being what it is), and hides the ugly concrete foundation. Because it doesn't support a huge static load, it is supported using the normal technique for garden decking, which is to bolt the deck bearers to upright posts set in holes full of concrete. The black cloth that can be seen under the bearers in the photo is permeable weed membrane. Its purpose is to stop weeds and grass growing up through the expansion gap between the deck boards (which looks very ugly). Plastic sheet won't do here, I think -- water will run down between the expansion gaps, and pool on top of the pastic sheet, where it will serve as a reservoir for evaporation onto the underside of the deck boards. Cost of this part of project:
Pressure treated timber £200
Exterior WBP plywood £100
Wood preserver £70
Deck boards £40
Weed barrier £20
Screws, bolts, other fixings £20
Vapour membrane £10
----
£460
Skeleton and outer shell
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| Outer shell of the rear wall, and completed deck |
Because I have no access to the rear of the building (it comes right up to the boundary of my property) at least some of the shell and skeleton had to be preassembled and raised into place. I've gone to town with the wood preserver on the rear shell plywood, because it is inaccessible for repairs when assembled.
For some reason, it turned out that the plywood floor panels as delivered were about about 30mm longer than the nominal 2440mm. For reasons which made sense at the time, but now escape me (maybe I was just feeling lazy), I decided not to cut them down to size, but install them as they were. The effect was to leave a small area of flat timber floor extending 20mm or so all the way around the bottom of the skeleton (the timbers for which were delivered the proper length). Deciding not to cut the floor panels to size turned out to be a mistake, for reasons explained below.
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| Start of roof construction. The large sheets of loosely-fastened plywood are to keep bits of the skeleton in place during construction |
So rather than aim for a roof that two large people could walk about on, I aimed for a joist size and spacing that would support one small adult (e.g., my wife) working on crawling boards to spread the load. This gave me a joist size of 3''x2'' at 16'' spacing (the span is about 8'6''). The roof joists are fastened with metal hangers for speed. The joists overhang at the front by about 18''; this is to keep rain off the front of the building, so the doors and windows can be open even when it is raining. This overhang does, as mentioned before, shift the centre of mass of the roof towards the front of the building, which has the effect of adding even more to the unequal front-to-back weight distribution.
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| Most of the outer shell in place |
With hindsight, the 2'' roof overhang at the sides and back is clearly not enough. It would be difficult to make it much larger, because the boundaries of the property are in the way. Rain tends to run down the side of the building, and pool on the remnant of the base that extends beyond the skeleton of the building. As mentioned before, allowing the base to remain slightly larger than the building was a mistake. -- it should have been slightly smaller if anything, so that rain could run down the sides and straight onto the ground. OK, so a thick bead of frame sealant stops water seeping under the floor timbers, but it's still a bad arrangement.
Given that the side walls of the building are not clad with anything, and there are joins in the plywood panels that comprise the walls, if rain lashed against the walls it probably could have the potential to seep through the small gaps between the plywood and the studs. Of course I've closed up these gaps with sealant, but the main protection against this problem is that fact that the boundary fence of the property comes almost up to the walls of the building, so rain doesn't really blow against the walls that much.
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| Windows in place and doorway framed |
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| Outer shell finished, hanging the doors |
Like the windows, I've sized the skeleton of the building to fit the doors, since I'm not too fussed about the door aperture size, and planing doors to size is a horrible job. Because the doors are only single-glazed, as they stand they will be a major source of heat loss from the building. I expect that it will be necessary eventually to `double glaze' the doors using polycarbonate panels.
Fitting the double doors was a horrible job and, with hindsight, one that I know I didn't do at all well. What I should have done was to prop the two doors up on the doorstep with temporary supports, then built the frame around them. Instead, I did my best to make the door frame perfectly rectangular using a ruler and a spirit level, not appreciating that the floor wasn't perfectly level. If the verticals of the door frame are even a few millimetres out of square, the two doors won't meet properly in the middle, which looks ghastly. It isn't even sufficient for the verticals to be perfectly parallel, if they aren't square to the doorstep. Moreover, the verticals need to be not only parallel, but in the same plane (in the front-to-back direction).
Imperfections in the door frame can be ironed out, up to a point, by placement of the hinges. However, more than a few millimetres can't easily be corrected this way. Cost of this part of project:
Pressure treated timber £160
Exterior WBP plywood £160
Roof felt £100
Doors £90
Windows £75
Bitumen adhesive £40
Wood preserver £35
Screws, bolts, other fixings £10
Joist hangers £10
----
£680
Finishing the exterior
With the shell finished, more or less, it was time to think about finishing the exterior. Happily, three sides of the building are more-or-less invisible, so I only had to finish the front.
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| Fitting the cladding and fascia boards |
|
| Is fitting cladding the most boring job in the world? Note that I've put the keyhole sufficiently high up that the children can't open the doors. Hehehe... |
Halved logs x 30 £75
Fascia boards £10
Door bolts £10
Night latch £10
Screws and fixings £10
----
£115
The total cost of the exterior of the building, not including
the foundations but including skids, comes to £1255, which
compares reasonably well with a prefabricated shed/summerhouse of
similar construction. Of course, that's costing my labour
(probably about 200 hours) at zero £/hr. As I said, I wouldn't
expect to make a cost saving building a shed -- it's in building a garden
office that there are savings to be made.
Cladding the interior
|
| Fitting the softwood cladding to the studs |
I decided to form the inner wall of the cavity with 6mm softwood cladding strings because it is relatively easy to work, and relatively light in weight. It also looks nice, and when it gets grubby it can be sandpapered, or washed down if varnished. Foil-backed plasterboard would have been a reasonable alternative -- cheaper and quick to fit. The problem with plasterboard is that it is relatively heavy: nearly ten times as heavy as 6mm softwood cladding for the same area. Moreover, it's not as flexible as wood, which would necessitate more or heavier studs to support it on.
The cladding I used is the cheapest tongue-and-grove variety. It is possible to glue the strips together to form boards, and then fasten the boards top and bottom like large panels. However, my experience is that cladding fastened this way tends to sag out from the walls when it gets hot, so I fastened each strip individually using the `hidden nail' technique. This involves nailing small pins obliquely through the tongue or edge of the grove, so it penetrates the stud at an angle. It is a horrible, time-consuming job, and I have to wonder whether it's worth the effort. As well as cladding the wall, I formed the ceiling with cladding as well, and insulated the ceiling in the same way as the walls. I did consider using 8x4 sheets of 6mm plywood for the ceiling, and I got as far as fastening a couple of sheets up to see what they looked like. For reasons I don't quite understand, they made the ceiling look much lower -- an effect that wasn't apparent with cladding. Of course, plywood would have been enormously cheaper, and taken a fraction of the time to fit. One concession I did make was to forego the hidden-nail fastening, and just nail through the wood. Hidden-nailing is horrible enough in ideal conditions, but on a ceiling it's just too ghastly for words.
|
| Stuffing the cavity with insulation |
It goes without saying that loft insulation needs to be handled with care, especially since it will probably need to be separated into thinner layers than it is supplied as. It's even more unpleasant to stuff into a cavity than it is to roll out in a loft, since much more manipulation is required.
When all the cladding was in place, I gave it two coats of thick polyeurethane varnish. Because it was February -- cold and damp -- the varnish took nearly a week to dry to the touch, and a further week for the fumes to stop being noxious. You can get low-odour varnish but, in my experience, it isn't as tough as the stinky varieties. With hindsight, cladding and insulating the interior of the building was by far the dullest, most time-consuming part of the job. I used about 200 cladding strips, nearly all of which had to be measured and cut, and then (except on the ceiling) hidden-nailed in up to seven places to the wall studs. Each nail had to be driven meticulously at the proper angle, using a punch to avoid damaging the cladding groves with the hammer. It is possible to obtain concealed mounting brackets for cladding, and they aren't all that expensive, but i didn't find they made the job all that much easier. Cost of this part of project:
Softwood cladding £205
Insulation £30 (estimated)
Rough sawn timber studs £20
Pins and screws £10
----
£265
Wiring
I should point out that by the time you read this, wiring a garden building will almost certainly be covered by the egregious Part P of the Building Regulations, so you'll need to involve the Building Control department of the Local Authority. Of course, you're going to want to ensure that your wiring conforms to BS7671 anyway, because it's a matter of life and death. Usual disclaimers apply -- don't attempt this unless you're absolutely certain you know what you're doing. If you don't know what the terms `disconnection time' and `voltage drop' mean, hire someone who does. The use to which a garden building will be put will have a major influence on how you derive a supply for it. If you'll be powering office-type computer equipment, and maybe a small fan heater, you won't need to do anything too arduous. If you're installing a sauna or a pool heater more work will be required. In general, if you can manage with a maximum current of 13 amps, you can take a fused spur off one of the socket outlet rings in the house. If you need more than 13 amps, you could perhaps take an unfused spur, and put additional MCB protection in the spur, but this is frowned on. The problem with this approach is that increases the risk that the power ring will be subject to continual overcurrents that are below the level that will trip a breaker. MCBs aren't designed to perform well in this kind of situation. For high-current applications, most likely the safest thing to do is to run a cable back to a spare way in the main distribution unit for the premises. You'll need to provide for earth leakage protection as well, probably using an RCD, if the power outlets in the garden building are likely to be used to supply portable appliances outdoors. Most modern properties have this protection already, at the main distribution unit.If the cable run from the house to the garden building is long (more than 40m or so), you might find that the limiting factor on the current available to the building is the voltage drop at the load end of the supply cable, not the way it is supplied from the house. BS7671 dictates that the voltage drop should be less than 4% at maxiumum load current. For example, steel-wired armoured cable (SWA) with 2.5 mm2 conductors can nominally support 27A in an ideal installation setup. But with a 40m run, the maximum current needs be less than 12A to meet voltage drop requirements. Of course you could install heavier SWA cable, but it's extremely expensive, horrible to install, and not well matched in size to the connection boxes you're likely to be want to use it with.
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| Distribution board and outlet. Note the fat SWA cable coming up through the floor |
The fact that I'm stuck with a relatively low maximum current makes a lot of design decisions easier. For example, I would be reluctant to run cable in the cavity between the inner and outer shells of the building if it had to carry a higher current. Because the cavity is completely stuffed with insulation, in places the cable is likely to be completely surrounded by it. In such circumstances BS7671 dictates that the cable be derated to 50% of its nominal current-carrying capacity. Because my maximum current is so far below the nominal capacity of the cable, this isn't a problem for my installation. If it were, I would have to consider installing cable in conduit on the surface of the inner walls -- something that I really wouldn't want to do. One thing that certainly merits careful consideration when wiring an outbuilding is waterproofing. BS7671 doesn't have a huge amount to say on this subject, beyond a general requirement to pay attention to the environmental conditions, which are likely to be rather hostile. However, so far as I can see, nothing in BS7671 requires that an outbuilding be wired as if the wiring were outdoors. That is, I can't see any particular requirement to use waterproof socket outlets, waterproof cable entries, armoured cabling, etc., provided that all reasonable precautions have been taken to prevent the entry of water into the electrical fittings.
As it happens, I have used splashproof (IP44) lightswitches and socket outlets, not because I'm worried about rainwater getting into the fittings, but because I'm aware that they are likely to be handled by people with damp hands. I've run ordinary flat twin-and-earth cable in the wall cavity; with tight-fitting gromets and a big blob of sealant at the cable entry point, I believe that water entry is effectively prevented in all normal situations. I wouldn't risk flush-mounting socket outlets, because I don't think an ordinary flush-mount patress box can be made sufficiently waterproof. I should also point out that I've built my office for year-round occupancy, and I'd know very quickly if water was entering the part of the structure where the wiring is.
If you run the wiring in the wall cavity, it may not be a terrifically good idea to put junction boxes in the cavity (even if waterproofing is not an issue, which it most likely will be) because they will be difficult to get to for maintenance. Please note that if you've got extraneous conductive parts -- copper pipes, structural metalwork, etc. -- you'll need to pay some atttention to maintaining equipotentiality between the metalwork and the supply earth. This subject is beyond the scope of this article.
SWA cable £50 (50m drum, not all used)
Flourescent luminaire x 2 £40
IP44 Socket outlets x 4 £40
Small consumer unit £15
MCBs £15
Flat twin-and-earth cable £10
IP44 lightswitch £10
Cable fixings £10
13A Spur unit £5
----
£195
Flooring
There really isn't an inexpensive way to make a nice-looking floor, which is washable and hard-wearing enough for a garden building. I considered and rejected carpet (washable types way too expensive), vinyl tiles (inexpensive ones too ugly), coconut matting (difficult to clean), painted plywood (difficult to clean and ugly), and a number of whackier alternatives that I'm too embarassed to mention. In the end I decided to use laminated wooden flooring, the cheapest I could get. This turned out to be Wickes' own brand 7mm beech-effect glueless flooring, at a whisker under £7 per square meter. The only problem with this stuff is that I don't expect it to be particularly hard-wearing -- the wood layer is tissue-paper thin, on top of a substrate of MDF. But it seems to be doing OK so far.Because the plywood main subfloor was not particularly even, I decided to use underlay under the main floor, and also a vapour membrane to prevent any moisture that manages to ooze under the walls from dampening the main floor. The edge of the vapour membrane is hidden under the skirting board, so the membrane forms a `tub' shape, with the laminated flooring and underlay in the bottom of the tub.
Laminated flooring cannot be laid right to the edge of the floor, because allowance has to be made for expansion. You need wedges (or offcuts of wood, which are cheaper) to stand the floor panels off a uniform distance from the walls. Glueless flooring needs to be hammered together, which is difficult at the very edges where there isn't clearance to swing a hammer. There's a specific tool for dealing with this situation -- a bit of bent steel which hooks over the edge of the flooring and provides a sticky-up plate to hit with the hammer. This tool usually comes in an installation kit that includes the wedges and a hammering block. You'll need the hammering block, because if you hit the edge of cheap laminated flooring with the hammer itself, it will collapse. Cost of this part of project:
Laminated flooring £75
Underlay £20
Installation kit £10
Vapour membrane £10
----
£115
Finishing and trim
|
| Windows are finished with architrave; skirting, bevel, and quadrant also visible |
Skirting board £40
Quadrant £52
Bevel £12
Stripwood £50
----
£154
The total cost of the interior, including wall and ceiling cladding,
insulation, flooring, electrical fittings, lights, and trim was
£729.
What I learned
OK, so the following may be obvious to some people, but even after ten years of hardcore DIY activity, including rennovating a delapidated house, they weren't obvious to me. Wood preserver is designed to soak right into wood. Obviously -- it wouldn't work otherwise. What this means is that if you spill coloured wood preserver on wood where it isn't supposed to go, you'll never get the colour out, even with sandpaper. I used green wood preserver for the parts of the building that wouldn't be clad, and which might just about be visible. But it's very obtrusive if you spill it on wood that is intended to remain wood-coloured. Bitumen dissolves in wood preserver solvent. In places where bitumenised roofing felt came into contact with timber that has recently been treated with wood preserver, the wood preserver dissolved the bitumen and soaked it up into the wood, leaving an ugly black stain that (naturally) permeates the entire thickness of the timber. Make sure wood that has been treated is fully dry before putting it near roofing materials. You can't screw two pieces of wood together so tightly that water cannot penetrate. Because wood, particularly unplaned wood, is never perfectly flat, the join between timbers will always be big enough to let some water through if it gets wet. There needs to be sufficient access to get some frame sealant around the join after construction. Water needs to drain away. If you allow water to pool anywhere, it will most likely find a way into the building. It's impossible to make a double door frame sufficiently accurate by measurement alone. The frame needs to be built around the doors. Building a double door frame is completely different from building a single door frame -- with a single door the battening around the door will hide quite substantial inaccuracies in the frame or the hanging. With a double door, it's all on display. Mixing concrete in large quantities is hard work. If you have to make a foundation, even in the form of concrete islands like mine, it's got to be worth hiring a mechanical mixer. I couldn't, because it wouldn't fit through the house. It takes much longer than you might think. It isn't the substantial construction that takes all the time, its (a) the preparation, and (b) the fiddly little jobs that you forget to account for. Preparation includes things like treating timber with wood preserver (it's slow, tiresome, and it takes ages to dry), digging and levelling ground, and carrying and stacking huge piles of timber. Fiddly little jobs include fitting door furniture, trimming and finishing roof felt, picking all the stupid barcode labels off everything (I just hate that), sealing up gaps between timbers. If you can't work on the job continuously, you also have to account for the time consumed by getting ready to work and tidying up, and the constant sweeping, cleaning, and tidying that are required to prevent the site turning into an eyesore. The quicker the roof goes up, the sooner you can use the building for storage. If you're working intermittently, it's much easier to be able to leave tools and materials in the partially-constructed building, than to get them out and put them away every time you want to work. But most tools and materials aren't particularly waterproof, so you'll need to have at least one wall and part of the roof up before you can leave stuff in the work area even overnight. If you have even a few roof joists up, you can make a temporary roof of (say) corrugated plastic sheeting, even if you're going to use something different for final roof. The time you'll save being able to leave tools and materials in the building more than compensates for the time taken to put up the temporary roof. But don't be tempted to put up part of a plywood roof -- ideally it all needs to go up together and be felted the same day. Roofing felt doesn't stick very well to wet plywood. October is a bad time to start work on a major outdoor DIY project. It gets dark early, it rains all the time, and it's cold. And if the work takes longer than you anticipated, you'll be trying to felt the roof in January when it's freezing. Some jobs are too big to do single-handed. However enthusiastic, strong, or competent you are, some jobs need more than one person -- it's as simple as that. Screwing the fascia boards to the overhanging roof rafters was a case in point. With one person to hold one end up, and another to hold the other end and screw the boards to the rafters, it would have been a five minute job. Single-handed it was a two-hour job. Longer, if you count the time I spent dressing he wound after I screwed my finger to one of the rafters. Yale-type night latches are designed for inward-opening doors. Shed doors typically open outwards, because there's more room outside than inside. If you fit an inward-opening latch on an outward opening door, you'll find that you need a key to close the door, but can open it without one. This, of course, is not ideal. I was able to dismantle the latch I bought and reverse the locking tang, but it still means that when you close the door, the locking tang strikes the wood, not the metal of the lock body. I'm not sure if anybody makes a night latch specifically for outward-opening doors.Conclusion -- how much did I save?
With hindsight, building the Kabin turned out to be a more ambitious undertaking than I really anticipated. What's more, I deliberately did the work during the winter, because I had other plans for the summer, and the days are rather short in December. I started work at the start of October 2004, and finally declared the job done at the end of March 2005. That's seven months from start to finish. My recollection is that I worked for three full weekends (7am Saturday to 6pm Sunday), a couple of Saturdays, and between 30 minutes and an hour about three evenings a week, with a break of three weeks over Christmas). This adds up to about 300 hours of work. A team of three people, working a typical 8-hour day, would have racked up these hours in about three weeks. Working alone, evenings and occasional weekends, comes to seven months.In fairness, when working out the cost saving over buying a commercial garden office, I really ought to account for the time I spent driving back and forth to timber yards and builders' merchants, searching the Web for suppliers, and poring over my computer doing the design and calculations. But I can't -- I really can't remember how long all this took. On the other hand, if I had opted for a commercial offering, I guess I'd have spent a considerable amount of time investigating manufacturers and comparing prices, so maybe it balances out. As for the financial cost:
Foundation £200
Frame and exterior £1255
Interior, electrics, and trim £729
----
Grand total £2184
(This price does not include the desk and shelving that can be
seen in some of the photos -- these were leftovers from another
job).
For the purposes of comparison with a commercial garden office,
the cost of the foundations should be excluded, since foundations
would be required in both cases. So the relevant figure is
1984.
It's hard to be sure how this bottom-line figure compares with a commercial garden office. Henly's MidiSpace has a similar internal size, and similar features, and costs about £12000 (assembled). But it doesn't have solid wood walls, floors, and ceiling (they're glassfibre and MDF). This price is, if anything, towards the cheaper end of the market.
So, by building my own, I estimate that I have saved at least £10000 -- a figure not to be sniffed at. Allowing 300 hours labour, this makes my `earnings' £33 per hour. All in all, not a bad deal.
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