, i had a chance of working in UK (nottingham, robin hood's place) before for almost a year and did saw a few house/bldg construction/renovation made of brick walls in my area. one thing i notice is that in some house, they don't just pile the bricks in just one row, they sometimes pile it in 2 rows (with a little space in between the 2 rows) and in an interlocking way - the length of the bricks they are using is definitely less than 12". i ask my officemates why and they said that it improves insulation and stability of the wall even without rebars for non-bearing walls - i guess it's because of their cold weather. cost will indeed be a factor in using bricks (better insulation compared to CHB) here in PH. one area i can think off is using it as walls for bedrooms where you will install an aircon ...

i think that the bricks (12"x4") you saw are not meant for walls but more for outside walkways in a backyard as their too long. if you want to use it for walls, better talk to a structural engineer and also do some more research in the internet ... cheers

Boo!

Hi @Boo-Semi-Retired! as usual i appreciate your replies here in PHM. (im learning a lot from you guys 🙂 ). ANyways, here's a link of the advertisement i saw. http://www.affordablecebu.com/board/real_estate/other/interlocking_bricks_for_sale/58-1-0-15053

the bricks are 12"x4" and it can be a direct substitute to CHB already (you can reinforce this with rebars). Do you think we can save costs with this @17php per piece?

Also with the brick laying -- how do we install conduits/pipes just in case the bricks are already in place. For CHB, i know we can just chisel a portion to lay additional pipes/wires and seal it off with plaster. how about for bricks? appreciate all the help!

i checked the website and the bricks are made of limestone (i guess mix with cement) and not the ordinary clay that bricks are normally made. i do have my old worksheet for my construction estimate computation, let me review it and i'll try and modify the wall computation using this brick specification. i'll post an update later.

as for the installation of conduits/pipes, same as with CHB, if it's inside the brick, then most people will simply cut (e.g. angle grinder with a masonry blade) a grove into the brick to accommodate the pvc pipe for the wiring. if it's not an issue to the owner, surface mounting the electrical wires using pvc moulding is cheap and practical. better yet, if you have the time, you can try out this (just thinking outside the box) and see if it's doable ... the bricks sold on the site has 2 holes in the center, perfect for conduit pipes - looks like it's about 1" in diameter. by aligning a set of bricks vertically (where you want to lay the pipes) when your piling it as a wall, then you already have a vertical hole from the top to the floor for your electrical wiring - you don't even have to use a pvc pipe as the bricks when piled will be strong enough to serve as the enclosure for the wiring 🙂 ... you can even look at how it can be done for horizontal wiring around a room 🙂 ... the trick is to design how the bricks are to piled so us to minimize wastage of some bricks, you will have to cut some bricks so that the holes of a set of bricks will be vertically aligned. as for the mortar, when piling, it can be easily remove by the person to keep the hole free from obstruction ... cheers

Boo!

as always, im encouraged by your out of the box yet common sense ideas here. thanks! ill wait for your worksheet update so we can compare notes on wall/plastering cost-savings if this brick system can do it. thanks! by the way, when you say we'll cut a grove in the brick to accomdate the pvc piping -- that means we'll cover the pipe with concrete plaster right?

yes, you need to cover it with concrete plaster or other materials. without any technical specs for the brick, my computation are simply approximation. per sqm of wall using this brick (12"x4"), these are the things you will consume:
- 0.0260 cubic meter of sand
- 0.0043 cubic meter of cement (approx 0.1529 bag of cement)
- 2m of 9mm bar (vertical and horizontal 1m each) - optional depending on the design
- 28.16 pieces of the 12"x4" brick

Notes:
1. brick size from the website is 12" x 4" (30cm x 10cm) ; no depth info for the brick in the website, and just looking at the photo, i'll assume it's also 4" ... so the size of the brick is 12" (length) x 4" (width) x 4" (depth) (30cm x 10cm x 10cm) ...

2. how many bricks per row. 30cm + 1.25cm (1/2" space between bricks for mortar) = 31.25cm for 1 brick with 1/2" (1.25cm) space after each brick ; 100cm / 31.25cm = so, approx you will need 3.2 bricks for a 1m single row of wall ...

3. how many rows of bricks. 10cm (4" height of brick) + 1.25cm (1/2" space in between rows) = 11.25cm height of each row ; 100cm / 11.25cm = 8.8 rows of bricks in a 1m high wall ...

4. total number of bricks needed for a 1 sqm of wall will be 3.2 x 8.8 = 28.16 bricks ...

as for the mortar for inside 1 brick, since we don't have any technical specs, i'll just assume the following base on the photos ... 2 holes which looks like 1"x1" in size with a depth of 3.5" (remove 1/2" depth of the grove). the grove (running across the brick) at the base which looks like about 1/2" high and 2" wide ... add to this the mortar for the rows and the space in between bricks ... total mortar area for 1 sqm of wall will be approx 0.0303 cubic meter (0.0260 + 0.0043) with a cement-sand ratio of 1:6. this is about 50% less mortar compared to using 12.5 of CHB in a 1 sqm wall (0.0621 cubic meter of mortar). the downside is the higher cost of each brick @ P17 compared to P7.25 for a CHB ...

hope this info helps ... cheers

Boo!

, as for the conduit pipes here is a simple process i just imagine of how you can use the brick holes for the wirings ... for simplicity, start the piling of the bricks from one column ...
1. for the odd rows, start the row with a complete brick when laying the bricks.
2. for the even rows, start the row with 1/2 of a brick (save the other half of the brick for later) when piling and then followed with all 1 brick.
3. with the above, the piled bricks will be interlace as you build the wall.
4. at the point in the wall where you want to put a vertical wiring, for all the even rows, put the other half of the brick. doing this will make the next brick in the rows all aligned vertically (top to bottom - 2 holes) for the wirings :-). after that brick, for all the even rows, use a 1/2 brick again to continue with your piling and then followed with whole bricks all throughout the row. once the wall is completed, the bricks will be interlace and the area of the wall for the wirings (either from the top or bottom) will look like a vertical column of bricks :-).
5. for horizontal wiring, it's better to use a pvc pipe that you put along the grove of the bricks.

hope this info helps ... cheers

Boo!

thanks for the enlightening posts! i was wondering based on your calculations above - assuming that this brick cost almost twice as much as CHB, but 50% less in mortar... and assuming no plastering on both sides of the wall (more labor time saved, and no more random bumpy palitada imperfections) - could this be a cheaper alternative to CHB construction? Really want to try this out if that's the case 🙂

let me try and do some actual costing based on my house construction notes before and share it here later 🙂 ... cheers

Boo!

, below is what i got for the cost computation of a 1 sqm wall based on the prices i got last year using CHB (4th quarter) here at tampakan, south cotobato. the difference in material cost is around 316.04 (assume price of brick is the same last year). if you add labor (minimum wage in region 12 for unskilled non-agricultural work is 275 per day) into the equation, then cost wise, its cheaper to use bricks than CHB - the bigger (e.g. wall areas) the project the greater is the savings because of the # of labor days required to complete the plastering activities. i think further savings can be achieve by consulting with a structural engineer to determine the minimum amount of rebar required for bricks compared to CHB - i assume their the same in this computation. from what i read before, clay bricks require less (or none) rebars for a wall, but these bricks are made of limestones, so i'm not sure if they are the same ... a contractor also needs to consider the learning curve of the worker in working with this type of material (bricks), especially in the cutting of the bricks - more wastage during the learning process which is more costlier since the price of each brick is quite high ... for owners, aside from preferences, most important is to really do a lot of research and consult a structural engineer as to the pros/cons of using bricks for wall instead of CHB ... hope this info helps to both owners and contractors 🙂 he he he ... cheers

1 sqm wall using CHB:
93.75 CHB @ 7.50 each for 12.5 pcs = 93.75
76.75 0.3133 bag of cement @ 245 per bag = 76.75
36.66 2m 9mm deformed rebar @ 110 each 6m = 36.66
29.64 0.1210 bag of cement @ 245 per bag for plastering both side = 29.64
----------
236.80 total material cost

1 sqm wall using limestone bricks (no need for plastering):
478.72 bricks @ 17 each for 28.16 pcs = 478.72
37.46 0.1529 bag of cement @ 245 per bag = 37.46
36.66 2m 9mm deformed rebar @ 110 each 6m = 36.66
----------
552.84 total material cost

Boo!

, FYI pre, my estimate above for cement in a CHB wall is wrong, its much lower. i posted the correct computation in this section in a new thread to share the info to the group. just review it :-). given that the cost difference between CHB and bricks are now much higher, the only way bricks can be cost effective to CHB is if you can get the bricks at a much lower cost ... at 17 each, its quite expensive 🙂 ... cheers

Boo!

im gonna save your computations as my basis for future projects 🙂 also based on your findings, i believe we can achieve more savings when we dont do any more plastering for both sides of the wall... thank you for sharing your expertise!

yup, your right. in my experience in our house construction, plastering is really one of the activity that will bust a construction estimate if you base your estimate on a 12mm (1/2") standard ... paano kasi, ang kapal mag lagay ng palitada ng mga workers ... there is something wrong in the process of how it's done locally here which results in too much waste. it can be improve, all that is needed are good contractors to analyze it 🙂 ... cheers

Boo!