Our Philippine House Project: Learn from our mistakes

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Our biggest Philippine house building blunders.  We don’t want to present our project as a paragon of perfection, so here we show what went wrong during our Philippine house construction project and why, in the hope that others can learn from our mistakes. Most of these photos also appear in other sections of the site.

No room for concrete in this post

No room for concrete in this column

This photo shows the top of a 15cm column trying to accommodate eight 16mm rebar from the roof beams and four 12mm rebar from the column. There is practically no room for concrete.  I ended up welding this tangle of rebar in the hope of gaining some strength from the rebar even if the concrete was minimal.  The post should have been sized by the engineers to be large enough to properly accommodate the rebar.  I told the engineer I wanted to demolish this column.  The engineer talked me out of it, however it should have been demolished and replaced with a larger column.

Demolishing just completed work

Demolishing just completed work

The engineers left out a support column needed to support a beam which they also left out.  One of the workers looked at the plans and saw the problem early on.  The engineers left out support for one end of a main roof truss.  We could not build in that defect, so we had to demolish a just constructed wall and wall footer (shown above) to allow us to pour a footer for the added column.  The concrete in the demolished footer was satisfyingly strong and resistant to demolition.

A column error corrected.

A column error corrected.

Workers laid block right up to rebar cage for columns, leaving inadequate room for the concrete portion of the column.  The block (which was filled with concrete) had to be cut back throughout the structure — a big waste of time.

Splicing error in roof beam rebar

Splicing error in roof beam rebar

This shows a rebar cage for the roof beam.  The splicing was done incorrectly.  No splicing plan was included with our drawings so the workers followed their own ideas which proved to be wrong.  See /our-philippine-house-project-rebar-splicing/ for all the gory details.  This particular rebar cage was redone three times before it was done correctly.  I don’t blame the workers.  In our opinion, a splicing plan should have been provided by the engineers.

bad_column

This column was demolished and replaced.   The concrete was too stony and dry, perhaps because I went too far in insisting that  not too much water be added to the concrete.  While almost everything one reads about concrete warn that water is the enemy of  concrete strength, as I learned, concrete should be wetter in hot conditions.  See the Portland Cement Association’s “Hot Weather Concreting” at http://www.cement.org/tech/basics_hot_weather.asp Many of the suggestions can only provoke a smile in the provincial Philippine situation, such as using liquid nitrogen cooled aggregates or cold water in mixing concrete, the suggestions about the importance of wetting forms and using a somewhat wetter mix make sense.  We also keep concrete beams wet for a few days.  It takes concrete thirty days to cure.

The effects of over vibration at the bottom of a column pour.

The effects of over vibration at the bottom of a column pour.

This defect was caused by my crew over-using the concrete vibrator.  The water and concrete slurry ran out of the bottom of the form, leaving behind the aggregate.  The crew tried to hide this from me by covering it with mortar.  I raked it out immediately.

Window openings were all made 10cm too small and had to be chiseled

Eight of the window openings were made 10cm too small and had to be chiseled so the windows would fit.

The welders were working at making the windows at the same time the window openings were being made.  Not great communication or oversight — including my own!

One step forward, two steps back

One step forward, two steps back

This is the aftermath of one of the more discouraging days.  The plans call for 12mm vertical rebar in the interior hollow block partition walls.  Since our walls are over ten feet high, this is especially important.  By the time I noticed (the foreman never noticed) that the crew had switched from using 12mm bars to the weaker 10mm bars, several courses of block had been laid.  I mulled this over and decided that I was not comfortable with the use of the 10mm bar and had all the work containing it demolished.  This amounted to three or four courses of block throughout the interior.  I could not get a satisfactory explanation of why the crew switched from 12mm to 10mm.  So we are paying for the original labor and materials , the demolition and new labor, block, cement and aggregate.  If I was not on-site, I never would have known about this problem.

It was amazing and a bit depressing to see how easy it is to demolish these walls with a hammer.  The 4″ block is weak, the mortar is weak.  If I was ever to build another house, I would use six inch block exclusively.  Don’t depend on 4″ walls for shear strength to resist lateral forces in an earthquake.

Column at edge of footer

Column at edge of footer

This shows a column rebar cage way off the center of the footer. Imagine sitting on the edge of your chair.  It’s tippy.  When this column is loaded, the tendency is for the footer to sag or tip.  The column was poured off center because the crew did not want to enlarge the footer excavation so that the column could be centered on the footer.  This thick concrete footer had to be broken up and repoured.

Clear span trusses

Clear span trusses

The engineers specified roof trusses which could span the house without supports — but why?   A simpler truss system using interior walls as mid-span support could have cost less.

Rebar Chair

Our workers did not understand the need to keep footer rebar positioned well up in the footer concrete rather than laying the rebar on the ground and pouring the footer over it.  We did not have any of the rebar chairs shown above so we used larger stones to raise the footer rebar above the ground before we poured.  Having the rebar on the ground in the bottom of the footer is a serious defect.

Nicely done footer and rebar cage sitting on the ground rather than raised into the concrete.

Nicely done footer and rebar cage but the footer rebar mat should be raised up so that it's in the middle of the footer concrete, not laying close to the bottom.

The carport forms come off showing yet more poor work

The carport forms come off showing yet more poor work.

How are such concrete problems repaired? We considered using epoxy but John Thede Joergensen’s suggestions seem right:

“I would use a thin plaster of fine sand and cement. 1:3 and wet, slam it on layer by layer thin layers at the time.The slamming is like blowing it on, and leave the sandcorn in the thin plaster, but like its vibrated in. It takes time and a good masonry hand to do it, but it is the same technique used when a concrete bridge is damaged by a truck, and the reinforcement is open. Then thin strong concrete is pumped and sprayed on to it layer by layer until its built up again. I don’t know if you can get the tool I think of there. I will find a picture and attached here. The floating plaster is balanced on the blade,and with a swing slammed on the surface. Practice on a plate first. Build it up, and let it dry in between till a point where you can “cut” remains away with the tool. Then use a sponge to make the surface smooth.”

I would use a thin plaster of fine sand and cement. 1:3 and wet, slam it on layer by layer thin layers at the time.
The slamming is like blowing it on, and leave the sandcorn in the thin plaster, but like its vibrated in. It takes time and a good masonry hand to do it. but it is the same techniq used when a concrete bridge is damaged by a truck, and the reinforcement is open. then thin strong concrete is pumped and sprayed on to it layer by layer until its build up again. I dont know if you can get the tool i think of there. I will find a picture and attach here. The floating plaster is balanced on the blade,and with a swing slammed on the surface. Practice on a plate first. Build it up, and let it dry inbetwen till a point where yuo can “cut” remains away with the tool. Then use a sponge to make the surface smooth.

Read all about our Philippine House building Project at /building-our-philippine-house-index/

Comments (26) Write a comment

  1. Is uncanny as I am the planning stage of doing the exact same thing in Cabatuan near Iloilo and am so grateful that I read a few of your articles. Was almost going to attempt to have it built from Australia where sister in law would oversee the construction and use the same foreman who built her place. How long was your wall in total Bob?

    Reply

    • Graham,

      The was was just shy of 200 lineal meters. Good luck with your project!

      Best wishes

      Bob and Carol

      Reply

  2. I think the engineer/s who made your plan is a no-no. He didn’t make sure the plans are really ready for actual construction. Many lowly engineers as well architects do give you plans at a lesser costs for building permit purposes but the real quality isn’t that dependable. If only you had a more reliable set of plans, these mistakes could be avoided. And if you hire an experienced engineer or architect to supervise the construction, it would be a lot more savings than trying to correct these mistakes on site.

    Reply

    • We pretty much agree with you, that a supervising architect can result in a better building. The problem for many foreigners (and Filipinos too) is identifying an architect with the desired talent, skills and integrity who puts the client’s interest first. Our preference would be to hire our own crew with a capable foreman, buy our own materials, and pay the architect to oversee the work.

      Reply

      • Hi Bob and Carol,

        This is a great blog you’ve got here. it’s actually very informative to architects and deisgners in a way that it highlights the practical items that concern pur clients.

        I am just curious, (because I am an architect) what you meant when you say it’s hard for foreigners to identify which architects are a good fit? Is this because of the lack of information and awareness, specially here in the Philippines to know where we architects and designers are? How would you say it’s different in the US?

        Tim

        Reply

  3. Good job sir, This could be of great help to architecture and engineering and others who have interest in the art of building construction.

    With regards to the footing bed bars or rebar mat according to ACI (American Concrete Instititute) all bars exposed to earth permanently should have a minimum cover of 75mm concrete protection.

    Reply

    • Alex,

      This is a very good point. My workers would have placed the rebar mat directly on the bottom of the hole, on the earth, with no concrete supporting the rebar mat. These are workers who have worked construction for years! Scary.

      Bob

      Reply

  4. I decided to use stud wall construction (germelina) with 3/4 marine plywood for our internal walls, mostly this was to cut down on the cost of concrete, although we centered the wooden walls about the concrete bathroom walls for strength.
    The internal walls were skimmed with a cement/masonry putty mix to hide the fact that its wood, visually you can’t tell the difference between this and the concrete walls so was a success, of course marine plywood not the greatest quality, so some of the exposed wood started to bloom with mold, but I treated this with Solignum clear, originally we used the Solignum brown which doesn’t cover mold.
    Interested in peoples thoughts on this as alternative to internal concrete walls
    Regards

    Reply

    • Wood walls? Termites. In 5 years you will be replacing those walls. Bite the bullet and do it now.

      Reply

      • Bruce, in case Ed actually used Gmelina lumber for the frames, he might be okay. Gmelina (as well as Teak or Narra) has contents that give it medium to strong resistance against termites. Having said that, at least annual thorough surveillance is mandatory.

        Reply

  5. Interesting to read about your problems in construction. As with most house construction in the Philippines you used Reinforced Masonry (RM) construction.
    An alternative type of construction that might have been more applicable is Confined Masonry (CM) construction. This is a form of earthquake construction started in Italy in 1906 it can be found in the Eastern Mediterranean, Indonesia, South America and Mexico were est 60% of houses use CM.

    In brief CM construction uses smaller tie-columns/beams to confine unreinforced masonry walls which is the main load bearing element. Though a well designed and constructed RM building is better a properly constructed CM building can survive a sever earthquake wit little or no damages and has many advantages; it simpler to construct and does not have to be so highly engineered, requires a less skilled construction crew, is more forgiving of mistakes in construction, is faster to build, uses less concrete and steel in its construction and is cheaper to construct.
    (see confinedmasonary.org for more info)

    Confined masonry construction has many advantages over restrained masonry construction and if worth serious consideration if you or (more likely) someone you know intends to build a house- Filipino building regulations permitting!

    Reply

    • Do you have a reference for any engineers/architects using the CM process here in the Philippines? If so would you be kind enough to email to us.

      Aloha & Salamat

      Reply

  6. That’s not a bad idea about a new career!! Now your builders know what you want there would be a lot of time and probably cost savings if they were to do this again. You know which guys were good and which war not. Use these guys as the basis of your team. Pay slightly higher rates but if thy screw up, no pay. I intend to do almost all of the wrk myself but I can’t do the digging and concrete work and I would gladly pay a little more to be sure that it was done properly. I think the narrative of all this work, captured in excellent detail is a tribute to you mate. Nice job all around.

    Reply

    • Thanks, but I really don’t want a new career. I’m retired. We promised ourselves that, in order to have a relaxing retirement in the Philippines, that we would not be involved in any business in the Philippines. Our own house was an exception.

      Reply

  7. Well i just finished reading most of your site. I have been here for 7 years and live in Cebu. In this time I have been involved in several construction projects.
    I feel a bit sorry that you went through some problems, but chalk it up to experience. I plan to build a house early next year, but since i have experience here and in the USA, I plan to run the whole show myself. It is no secret that here you must be like a mean old headmaster with a big stick….the second you leave the room, things will be shoddy, even form the most experienced contractor…..why is that, you ask?….simply put it is because shoddy work is the norm and acceptable to the locals.
    Ever watched a local chip away at a perfectly fine, week old cement slab so he could install a water pipe? Of course you have! Insane !…and he wants me to pay the labor !
    I know I am no expert in construction, and i am sure to have some mistakes, but one thing for sure, I plan on planning well, and watching every move. By the way, nice house!

    Reply

    • Michael,

      I guess it’s because these guys have never had any training in their trade and in most situations where they have worked, cutting corners, saving money and speed are what is wanted. If you want things done your way you have to be there every second. I even hated going to town to get materials for fear of what would happen while I was gone. Basically I arrived at the job site at 7am and left at 5:30pm. That said, I am very grateful to my workers. They tolerated all my criticism and worked hard. They were very honest decent guys. All this pain resulted in a sturdy house and I often think of my workers with appreciation and affection.

      I’m sure you’ll have many frustrations but with your experience you’ll end up with a well-built house.

      Good luck!

      Bob

      Reply

  8. I admire your determination in bldg such a nice house so far away from civilization. I currently live in Laguna in Binan city. With a bit of faith and patience, my own family house will be built soon in 150 days. Yet, I’m using a different bldg technique that requires to be a more presice job and there is no margin for errors. Less wood and no hollow blocks at all.

    Im using Sterling insulated plasma Panels with their own set of blue prints, the factory is located in calamba. Due to the deed of restrictions of the subdivison, I don’t have the luxury or not many choices of colors for the roofing, Which color will you recommend me?
    I will be using long metal spams, all this is in accord with my budget.

    Reply

    • Our roofing came from DN Steel, which I believe to a a nation wide distributor. I’d suggest the whitest material they have. I think that would be “ivory” or “beige”. Be sure to put reflective foil underneath.

      Good luck!

      Bob
      http://

      Reply

    • David,
      What is your experience with the Sterling’s Plaswall panel type construction. I contacted them and their price is very reasonable in comparison with the CHB construction. How long did it take to construct your home? Were the panels of good quality and did you have to purchase their mixer and pump? They are quoting a supervision for relatively high cost 750 PHP/day + accomodation and food. Was your master carpenter capable to follow the rest of the construction, which is hanled in reverse way, that is, footings, piping and conduit first then the slab, and then the panels which are filled with concrete mixture.
      Can you please share your experience.
      Regards and happy holidays.
      Jan

      Reply

    • To Dave Vargas,
      Thanks your input on “Sterling insulated plasma Panels’. I plan on building our house here in San Pablo City, Laguna within the next few months. I’ve never heard of Sterling insulated plasma Panels. Can you please provide ore info on this (price, benefit compared to hollow blocks, company, etc.) I googled it but could not find it. Calamba is only an hour from San Pablo City. Please reply to amorej1@hotmail.com.
      Thank you and your reply will be much appreciated.
      J. Amore

      Reply

  9. Hi Bob. Many thanks for you great site, we are planning to build in Maigao in about 4-5 years time, your site has given me a lot of help, especially the comments you see on the web about solid concrete walls vs hollow block.

    Reply

  10. Hi Bob, i’ve told some friends about you and your gifts in journalism, photography, civil construction, and more. Our church will open a preschool in June. For our classroom, bamboo walls will be installed on our existing open social hall. Your finely crafted bamboo/nipa hut is an inspiration. Great photos. Thanks. godfrey “gad”

    Reply

  11. Bob, I think you are going to have a new career as engineer/contractor for every expat wanting to build a house. You have been outstanding in your attention to detail and thoroughness in this project. I am very impressed with what you are doing. I am anxious to see pictures when the finishing process starts. Good job Bob. Ron

    Reply

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