Life in a Dol house
2017 - Week 44

Watching concrete dry

I had one of those reminders this week that Christmas is just around the corner

 - actually just 8 weeks from today - when I went to the supermarket and came home with a bulk pack of sparkling water, resplendent in its winter wrapping - snow crystals red ribbon and red leaved Poinsettia.

It will be December before anything else Christmasy appears in the shops here, but the reminder has been noted. I have a lot that I want to achieve between now and then.

We have had a Bura, the cold north wind from the European Plain this week, which has dropped the temperature somewhat. 

It is still lovely in the sunshine during the day, but the sun's azimuth is dropping noticeably.

Or maybe it is because I am taking more notice as I record the sunlit hours on my largest south facing roof. 

A replacement UV sensor was delivered from Italy this week for my weather station, so I am now reporting UV levels on my weather website as well as all the usual weather data. 

At this time of year, with the sun fairly low in the sky, even at mid day - 

We are only a few weeks from the Winter Solstice - the maximum UV index value should be between 1 and 3 and I am getting a reading of 1.0 or below.

Most of the current photo-voltaic roof panels use the visible light spectrum of 380 to 750Nm, but there are new generation panels - more expensive of course - which use both the low end UV light and the high end IR, both of which are outside the visible spectrum. 

Whilst my recording of sunlight hours will give the maximum theoretical hours of sunlight, the UV sensor will add more information, but because the sensor is horizontal, rather than in a plane aligned to the roof angle, it will not give me the actual daily total of sunlight on the roof.

However, even these two figures will add considerably to the knowledge I will have on how much electricity my roof is capable of generating in a given period of time.

A little rain on Sunday night, coupled with a thunderstorm refreshed everything and now as I look out of the dining room window, the island of Brač to the north is illuminated by the setting sun, whereas here in Dol, it disappeared behind the hill to the south of my home at exactly 16:00, more than a couple of hours ago. 

Even so between the 9th October when I started recording sunshine hours and today, I have had a total of 155 hours, and during the same time have used 37 kWh of electricity.

I am at the point of moving into my newly renovated study. I was looking for some shelves which I know I have in the store, but I cannot locate all of them. 

They are not lost, I just don't know where they are!

I managed to fix one to the wall above my desk, although I struggled to neatly drill into the hard stones behind the soft lime plaster.

The drill bit kept slipping off the stone and enlarging the hole, but I eventually made it secure. I think this weekend will be when I move the computers and peripherals into place in their new home.

Part of the problem is having a number of specialist items - large format and 35mm photo scanners, document readers, a couple of printers etc., all of which will need connecting.

Then there is the file server to move and set up along with a lot of cables. I decided that I would do it after writing up and posting the blog, then I have another week to trouble shoot the network and system, just in case something goes wrong.

The builders have been here all week converting the old cottage loft into habitable space. 

Monday was spent in building the modular formwork for the reinforced concrete ring beam on the top of the walls, then installing the steel rebar box beams inside the construction.

​I had to construct a wiring loom for the ring main, so that it was installed in the blue conduit, inside the ringbeam. 

There is nothing too complicated in this loom.
​Whilst the builder has suggested that the new room, which measures 20 square meters, would make a very useful habitable space.


 I just want it for dry and secure storage at the moment.

On Tuesday the site was a hive of industry, with one man working the concrete batch plant, one man literally running up and down the wooden "ski jump" with barrows of cement, and two people filling the 30 x 30 centimetre formwork for the ring beam.

​It was all finished by lunch time, so I started on the cleanup operation inside the downstairs rooms of the cottage. Dust and debris has gone every where. This is really just the initial clean, I will need to remove everything at some point so that the walls and floors can be completely renewed and a damp proof membrane installed as well. But at least it got rid of the worst.

Wednesday they were working off site, to allow the concrete to set. So I spent the day watching the concrete dry.

Actually it is a chemical reaction that forms a solid matrix when the water and cement react chemically and bind around the hard aggregate and rebar. 

It does take a little time before the formwork can be safely removed, and more still until the concrete achieves maximum stiffness and solidity. 


But as much of the remaining ancient Rome was built with concrete, I have high hopes it will see me out.

On Thursday morning the wooden formwork was removed and the first of the rafters was attached to the ridge beam.

Then more formwork was constructed to create the concrete eaves.


​On Friday, more concrete was poured to create the overhang for the rain water gutters and on Saturday the roof went on.

​Starting from the inside, there is a damp proof membrane held in place with wooden lats, 20 cm of insulation, then a layer of interlocking OSB, followed by 2 cm foam core insulation, then more lats which the roof tiles will be fixed to.

At the end of the week, the roof is waterproof and ready for tiling next week. 

The Velux window has been delivered, the dormer windows have been constructed and I have made up the wiring looms for the lighting, which I will install tomorrow.

I am close enough to completion, that I am planning what I will move into the store room first! There is nothing like having a plan, even if in the end I don't follow it word for word.  No plan survives the first encounter with reality...

Around the garden, there are a lot of Preying Mantis, Sphodromantis viridis. I even encountered one on the weather station mast, at the apex of the roof hiding in the shade of the antenna mast.

​There are a number of spiders up on the mast - their webs have actually stopped the anemometer cups spinning a couple of times - so I presume the Mantis have been feeding there.

I am still harvesting tomatoes and also an occasional Kiwano Melon, Cucumis metuliferus which when added to a smoothie with a Persimmon make a most refreshing drink.

​Even at this late stage of the year, the recent rains have brought plants into flower. This is a wild Gladioli,

which is close to my kitchen window.​

Norman