All Need To Know About The Oversite When Building An Extension

The Oversite on the Construction of an Extension

Nev stood up, took a final slug of his tea and nonchalantly tossed the final dregs into the geraniums.

The dull aching in his lower back told him his day was nearly over. It was a situation he had found himself in many times before, but it was a situation he liked.

He was a contented man. Much of the hard work had been done now and he could reflect on his achievements with a quiet satisfaction.

He knew it wasn’t over, the customers knew it wasn’t over, but it had been a damn good show thus far.

3.45pm. He had better get a move on. It would be dark soon. This was no time for patting yourself on the back, he thought.

But still he found his mind wandering back to what had come before. He was up to damp course level with the brickwork. He had excavated the area between the brickwork long and hard.

The sweat had cascaded from his brow as he had compacted the broken hardcore. He had felt like an actor in an anti-perspirant commercial – “Sweaty Builder for men – it’ll never let you down.”

The architect's drawings had stated 100mm of compacted broken hardcore and that was what Nev was determined to give his customers.

No cracking concrete slab for them. Nev had a good reputation around these parts and no shoddy workmanship was going to ruin his good name.

Next came the 50mm of blinding sand. This was the easy bit for Nev but it had the very important function of ensuring that the Visqueen damp proof membrane wasn’t punctured in any way by the hardcore and thus remained watertight.

Next up for Nev was the Visqueen itself. He had a roll in the van and remembered how he had laid it out carefully to cover the entire area, lapped it up the brickwork and folded over the damp proof course of the brickwork.

No way was he going to have moisture penetrating his lovely new slab. This, he thought, was a DPM work of art.

Then it was the insulation. Nev remembered how the architect's drawings had stated 100mm Celotex/Kingspan.

A little over the top he had thought but who was he to argue with the architect?

Anyway, it would prevent more of that precious heat from disappearing into the ground below. Got to be worth it in the long run, he figured.

Some people were saying these days that another layer of damp proof membrane had to be placed over the insulation so as to stop the concrete from reacting with the silver covering on the Celotex/Kingspan.

It was news to him but he did it anyway. Better safe than sorry. Probably someone in a white coat in a technical department somewhere covering their backsides, Nev thought.

Some other builders liked to put their Celotex insulation over the concrete slab but below the screed and that was fair enough he thought. Horses for courses.

Whatever floats your boat as long as the Building Inspector gives you the thumbs up.

The concrete had arrived bright and early just as Nev had planned. He had allowed for a slab of 150mm thickness, tamped well down and levelled off. Good, strong and solid, just like Nev himself.

No cracking, no call backs. Just the way he liked it. He had even considered putting in some concrete reinforcing mesh to add further strength but had opted not to, as the job was a comparatively small one, and the Architect hadn’t seen the need.

4.45pm and the light was starting to fade. Nev hunkered down with his dustpan and brush and swept away the last of the dust from his rapidly-hardening slab.

Tomorrow was another day. The drawings had said 75mm of screed to be laid on top of the concrete slab. Fair enough Nev thought, but there was no way he was doing that tomorrow.

He would get on with the brickwork. If he did the screed tomorrow, it would surely get damaged during the ensuing building work and he didn’t want to do the job twice.

Anyway, the concrete would give him a nice, solid and level base on which to work. Best leave it ‘til further down the line he thought, and with that he locked up, jumped into the van and eased into the evening rush hour traffic his headlights bouncing over the tarmac ahead.

Nev headed to the pub and got completely hammered.