Self-build New extension

ifah

Hi folks,

Just looking for some advice on possible savings to do a self-build of a reasonably simple extension in North Dublin as opposed to paying the €150 per sq ft that some builders are looking for.

We intend building a simple rectangular room with an A roof extending out from our current patio door area. Total new floor area will be ~ 380 sq ft. At this price builders are estimating between 40k and 50k which I think is daft !!

So I'm thinking about the direct labour route - My dad and brother are carpenters (based in Galway) so the roof and second fix are no problem and I am friendly with a plumber and electrician to do the simple fit out that we require from them. I would be looking at getting an estimate of costs for foundation/subfloor/block laying and also plastering. Does anyone have any estimates for this type of work ?

Also is someone could point me in the direction of who I could approach for quotes I would be very grateful.

One last point - would it be necessary to get plans drawn up or would instructions be sufficient to the tradesmen involved ??

Cheers,
ifah

Victor

I'm not certain, but for that size you will probably need planning permisison, so you will need drawings.

For pricing an extension, shape is as important as size. Is it 20' x 18' (56'-58' of gutting) or 2' x 190'? (194'-382' of gutting)?

All tradesmen will prefer to work off drawings, if they don't have them (a) they are relying on word of mouth (b) you will end up responsible for all mistakes (c) people will charge more because they see greater risks involved.

Mugs game to be honest.

ifah

Hi Victor,

I don't need planning permission - it's under the 40sq m restriction and is completely at the back of the house.

Also shape wise it would be approx 7m * 4.5m.

When I meant would tradesmen need drawings, I meant architect level drawings or would a CAD laid out drawing suffice given that there are no complications - just straight walls.

Rooferpete - I see you recommended a plasterer previously - could I get those details from you ?
Also anyone know a blocklayer and someone to do foundations/subfloor ?

Cheers,
ifah

lensman

ifah wrote:

Hi Victor,

I don't need planning permission - it's under the 40sq m restriction and is completely at the back of the house.

Also shape wise it would be approx 7m * 4.5m.

When I meant would tradesmen need drawings, I meant architect level drawings or would a CAD laid out drawing suffice given that there are no complications - just straight walls.

Rooferpete - I see you recommended a plasterer previously - could I get those details from you ?
Also anyone know a blocklayer and someone to do foundations/subfloor ?

Cheers,
ifah

Hi ifah,
I had a bricklayer in last Saturday, similar type job to yours but not as big 240sq ft,...a 3 wall an add on extension to the back of my home,..the foundations were ready so he started to lay 2 rows of 4" solids to dpc at 8:30, and up went the walls using 9" cavitys,..break for tea & sambo's at 12:00 then continued the walls until the last block was laid at 16:00.
he was recommended to me by a trusted friend and I found him to be 100%
reliable and very reasonable price wise.
He called to the house the previous week to discuss what I wanted and to look at the plans he also told me the amount of material I needed,..bricks, blocks, heads, cills, sand and cement, also told me to order from J&K Supplies, The Ranch, Ballyfermot,..Tel:6268610/6265862 as they are the cheapest around.
I will PM'd his details to you.
Good luck.

ifah

hi lensman,

thanks for the pm - will give him a bell later.

Just for the record - did you do the foundations yourself or did someone do it for you ?

Also why did you go for 9" cavity blocks ? Are you going to slab the inside or plaster it ?

Also when you say reasonable - can you give a ballpark for what he charged and how much materials were ?

thanks,
ifah

pbergin

ifah wrote:

Hi Victor,

I don't need planning permission - it's under the 40sq m restriction and is completely at the back of the house.

Its not just as simple as under 40sp m, I believe there are different rules if your house is terraced, semi-detached, detached etc also depends if any other extensions have already been added and I also think there might be some rule about leaving certain amount of your garden.

lensman

FOUNDATIONS..
I have 5 son's who cost me a fortune over the years so it was pay back time,..
I gave them pick's & shovels and pointed to the muck.
INSIDE WALLS.
Slabed with foam backed chalkboard on 2"x1" battons, light plaster coat to cover over joints and corners.
Materials.
350 x 9" cavity's,...rising walls.
100 x 4" solids,..to rows laid flat upto dpc.
36 x 3" solids,..needed for around windows and at roof level.
3 x 5ft heads
3 x 4'6" cills
2 ton sand,.. droped in 1 ton bags
20 bags cement
€885, no del charge...:)

Bricky arrived with electric mixer,..scafolding bars and planks, he is on his own so we kept him supplied with blocks and mortor.

Corkey123

Ifah

I found myself in the same situation you and elected to build myself. My experience was if you do it by direct labour you will save up to 40%-50%, however the time frame will stretch by 200%-300%.

If you intent to do the ground work your self i.e foundations etc, you will have to consider digging equipment, if its a terrace you may need to dig the foundation the hard way. You will need to get to the orinigal foundations and possible a foot lower. Yoy will then require concrete as your base, I hope you have a side enterence for this. You will require 1 foot deep and 2 times the wide of the block, (cavity most likely)

If the entersion is at the back of the house you may have to consider if the main waste is under the new construction, if so you will need to take precautions to protect it. Whn the bloack word is done for the foundation you will need to fill it with hardcore, put in some steel reenforcement, dampcourse and arrange to concrete to the level. All services such as drains, connections to waste etc. will need to be consider before you do this.

Thats just the ground work before you actually build the extension. Off with you now and lets know how you get on.

Apip99

Hell those materials do sound cheep.

Out of interest how much did the foundations cost to fill? I guess in a way with out being rude I'd like to ask a ball park figure of the total cost. (No need to answer, just curious)

Does any one know of a useful web side for a step by step guide of building an extension?

And Lensman, can you PM the number of the guy you used for the work.

Thanks,

Pip

lensman

Apip99 wrote:

Hell those materials do sound cheep.

Out of interest how much did the foundations cost to fill? I guess in a way with out being rude I'd like to ask a ball park figure of the total cost. (No need to answer, just curious)

Does any one know of a useful web side for a step by step guide of building an extension?

And Lensman, can you PM the number of the guy you used for the work.

Thanks,

Pip

5 Cubic mtrs at €95 per mtr, not the cheapest but the guy dropped extra, enough to do a 3ft path around which I was ready for,..;)
I have a back lane behind the house but it's not wide enough for a large truck
so I had to pay €350 to have the concret pumped over the roof,..:(
also see here http://www.iaosb.com/html/cost_of_construction.html
and here http://www.crescentbs.com/calculator.htm
and here http://www.blocklayer.com/Roof/RoofEng.aspx