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E.0-2. Advice for Clients Who Want a "Cheap" House

M 관리자 1 5,680 2017.11.25 11:50

A regular (leaky) House is Reality; A Passive House is an Ideal; The Distance between the Two.  

 

This Technical Note is not a scientific article. An effort was made to avoid numbers and units, and rather than using actual photographs, easy to understand diagrams have been adapted. 

  

How much does it cost to build a house? Costs can range anywhere from 2,000,000 ~ 10,000,000KW/py. 

 

*note

"py" is the traditional area unit of Korea, 1py = 3.3 square meters. 

It reads "pyong".


so, [1,000,000 KW/py = 1,000,000KW/3.3square meter 

= 892USD/sm =  27USD/sf]  - 2017.11 exchange rate

 

  

What then accounts for the nearly 4 times difference in estimated cost?

 

What is at the root of expensive houses? Design? Expensive materials? A super sturdy structure? Exquisite imported sinks? A wide variety of detailed cabinetry? Eco-friendliness?

 

And why are cheap houses cheap? Was no profit made from construction? There was free help from a friend? A cheap price just happens to be what it really costs?

 

Why does this difference exist between expensive and cheap houses?

 

What in fact is an appropriate cost of construction? 3,000,000KW/py? 4,000,000KW/py? 5,000,000KW/py? 

 

There is a saying that building a single detached house requires LUCK. It is not entirely inaccurate. (Sad to say.) When referring to luck, houses that range from 2,000,000 ~3,000,000KW/py do not apply. Houses that range from 8,000,000 ~ 10,000,000KW/py also do not apply. Because houses in the first range have no room for choice and houses in the latter range have a lot of choices, with a lot of experts helping in these choices.

 

The problem area is the range in between, in particular the 4,000,000 ~ 6,000,000KW/py range. Of course there are many choices possible in this range; however, there are also many experts flocking to this range as well. In this range, there is no one who is not an expert. This is where the problem begins. "Everyone claims to be an expert and the Client has no way to differentiate." This is where the enigmatic Lady Luck makes her grand appearance.

 

PHIKO has no way to defeat this reality. We can only witness and try to ameliorate the situation by posting and organizing relevant advice and the notes of researchers and practitioners on our website.

  

All Clients want a cheap house or more accurately, a good house for a bargain. It is human nature, so there is no one to blame. This article is a short summary meant to help the "Owner who wants to build a house cheaply." This section will also try to add content continuously over time through the advice posted by you, our readers.

 

 

Things to Avoid when trying to build a House Cheaply

  

1. Getting an Acquaintance to do the Job

Of course, if the acquaintance is someone with whom you no longer wish to have any contact with, go for it. Because, that is exactly what will happen. 

  

 

2. Flat Roofs

A flat roof is a very finicky roof. Not only is it difficult to waterproof, but maintenance and repair, and more fundamentally, to build properly in the first place, is just plain very difficult. Half of all problems that arise after completion of construction arise from flat roofs.

  

 

3. The Second Floor

Unless there is a specific reason, if you are planning a small house, make it single rather than double story. The structure of a second floor is not as simple as it would seem. Just because the neighbors all have a second or more floors, it does not change this fact. If you knew how much more it costs to raise the mechanical, electrical and plumbing lines just one floor you may be quite surprised. 

 

And, at least 2py (6.6sm or 71sf) are lost to the staircase. If you consider 2py on the first and second floors, a total of 4py, or the area of one large room is lost. By placing a bathroom under the stairs you are not saving any space. You are still left with the lost area and an uncomfortable bathroom.

 

However, if you consider the building code aspects of the FAR (Floor to Area Ratio, Building Coverage Ratio) and cost of land, a single story may not be the right answer either. What we are referring to here is the increased loss that is incurred when a homeowner insists upon a two-story home when there is enough land for an ample single story. 

To those who do decide on two stories, a magical phenomenon typically occurs, where the building area increases, which in turn is reflected in a higher overall building cost.

 

4. The Big Room 

Of all the sections, this one is the most nebulous. The topic is not referring to the total area of a house but to the relative sizes of each room. In reality, it is difficult for a non-architect Client to really grasp the aspect of room size. Especially when looking at the rooms in a floor plan, the rooms just seem to feel small. For example, a 3m x 4m room is a surprisingly large room. 

 

Below is an image of a person inside a 3m x 4m room. If it is to function as a bedroom, primarily for sleeping, then the smaller it is, the better. If we can minimize the size of each room to fit its function, then we can reduce the footprint of the entire house, without much worry. The subtracted area can be allocated to the living room or to storage space or better yet, left out entirely, for a smaller, cheaper house. 

 

Drawing1 Model (1).jpg 

 

  

5. The Basement

This too, is an element to forego. Basements are difficult for even large construction companies to get right. But if you absolutely want one, or you absolutely need one… then still, please think again. Of the 10 years one will age while building a house, 3 will be due to the basement. Caused by any tiny errors made during the design process or during construction, you will be inundated with mold and leaks; and finding the solution can cost as much as it took to build the darn basement.

 

 

6. Cheap Faucets and Door Handles

One should use good faucets because faucets and door handles are the architectural products that will get the most wear and tear in a house. Of course, expensive faucets are good. But, with the exception of imports, the cost of even an expensive faucet is peanuts compared to the cost of the entire house.

  

 

7. Metal Entry Doors (aluminum excluded)

Apartment unit entry doors (that do not get rained on) typically are specified with (unnecessary) metal doors. Metal doors are not appropriate for single detached homes either.  Metal doors that are exposed to the outside elements will begin to rust in no time, with the exception of aluminum doors that do not corrode; however, they are one of the things that are forsaken as too expensive when building a thrifty home.

 

Recently an ABS door of comparable quality to a German entry door has begun production in Korea at a cost of 3,000,000KW. Psychologically, the cost may turn you away; however, it is worth every penny.

 

 

8. Double Pane Glass that has been filled with Argon Gas manually

If this product has been made properly, then by all means use it; however, in Korea, as of yet, for thriftily built single detached homes, I have yet to find argon filled double pane glass windows that perform properly. In other words, quality control inspections are forgone for the majority of such windows delivered to small buildings, and even if they have been filled with argon gas, for the most part, the gas leaks out in no time. 

Since argon gas is invisible to the naked eye, there is no way for the Client to see if it is in place or not. The best we can do for now is when placing our order, ask whether the gas has been filled manually or mechanically. Of course the answer will be in line with the pamphlet, namely, it was mechanically filled; however, there is a big difference whether or not one asked or not before date of purchase, in the event of a dispute.

And even if the pamphlet states a mechanical filling procedure, depending on factory conditions, materials being used, and setting values on the machinery, argon gas may easily leak. It is a pity that we are left to doubt everything.  

 

 

 

9. The Aluminum Window

Due to its high price tag, folks embarking on building their affordable single detached home will find it difficult to specify aluminum windows; however, a rather affordable type has come on the market - namely, a sliding type. The local market term is "sash window" and at all costs this type should be avoided when building your home.

Compared to PVC, aluminum conducts heat about 1500 times more. Naturally condensation cannot be avoided.

There is an aluminum window type that uses an insulating bar (see diagram), but this too is not recommended as in the winter, the relative humidity inside is higher. Of course, there are high performance aluminum windows but they are much more expensive and it is difficult for the average consumer to determine which window is performing well.

Now, as you are well aware, there is a window rating system in place. Since we can now select windows according to this rating system, it has become easier to make selections and if we look closely at the windows listed and compare their performance values, we can see that for the same rating level the performance of PVC frames are better.

 

삽도.jpg  

 

10. Silk Wallpaper (= PVC Wallpaper)

What we commonly call Silk Wallpaper should be called vinyl or more accurately, synthetic resin wallpaper. A fancy name is a part of the marketing, but stating the actual properties helps in judging the market.

To state the biggest problem, when condensation forms in the wall, moisture cannot penetrate through the synthetic resin structure; so even when the mold forms in between the wall and the wallpaper, it takes a very long time before the Client is even aware of its existence. Meaning, even if the mold problem is extreme, it will not come through the wallpaper but continue to propagate underneath; and not until the condensate spreads to the ground and the wallpaper is peeled off, will an unbearable amount of mold spores be exposed.

After becoming aware of the mold problem and a remedy is sought, too much time will have passed since Completion of Construction and the contractor will be long out of touch; and even if you do get in touch, no one will readily come. 

 

It takes a very long time for a concrete building to dry. If the synthetic resin wallpaper is installed beforehand, even if there is no condensation, mold spores will germinate. Furthermore, because it is made of synthetic resin, to prevent hazardous substances to emit, an eco-friendly upgrade type will inevitably be more expensive. It is unlikely that this latter type will be used in a modest single family home.

 

Synthetic resin wallpaper is installed with adhesive at the top and bottom. The middle area is unattached to the wall. So even if a crack appears in the wall, no one will know. In addition, because there is a space between the wallpaper and the wall, any unevenness in the wall plane is concealed. Therefore, to be extreme, even if the wall surface is quite rough and uneven, no one will know. In contrast, because composite paper  (합지벽지) wallpaper is glued to the entire wall, unless the wall is very even, it will look quite unsightly. So, whether the base construction was done well or not will be visually easy to determine. Therefore, unless there is a special reason, just use composite paper wallpaper. Using composite wallpaper will not guarantee that mold will not appear in the case of a poorly built house; however, because the mold will appear quickly, repairs will be able to be demanded within the warranty period.

   

 

 

11. Installation of Photovoltaic Power Generation Equipment on Asphalt Shingle or Tile Roofs

Also to be avoided, the reason being that in order to attach PV panels to a roof, metal bracket screws must penetrate and compromise the waterproofing membrane. Typically, PV installers will then fill the gap with silicone; however, this is far from a long-term solution.

 

If PV Panels are to be installed on a sloping roof, then it must be a metal (metal tiles excluded) standing seam roof. If you look at the photos below you will be able to see how to properly install PV panels without damaging the waterproofing membrane. Since the panels are fixed to the roof by bolts to the protruding standing metal seam, there is a low probability of associating its installation to any damage to the waterproofing layer.

 

PICT0246.jpg 

PICT0261.jpg 

 

Please refer to the link below to see how PV panels are installed on asphalt shingle or tile roofs

http://www.phiko.kr/bbs/board.php?bo_table=z3_01&wr_id=722

 

 

12. Excessive Living Room Lighting

It is hard to know before you build it, but when you use it, after Completion of Construction, 1/3rd of living room lights are not used. Moreover, if all of these lights are operated with one switch, then you have a problem. For the most part, four fluorescent bulbs are sufficient to light a living room. In particular, accent lighting is a good way to create a different, lively or soft atmosphere in the living room; but, after construction you will probably only use it once or twice.

 

If you must have a lot of lighting regardless of cost, then I strongly recommend that you group them into separate clusters each with a separate switch.

 

 

13. Verify the Core Material Grade of the Furniture

Fine dust particles can influence the IAQ (indoor air quality), but the Core Material Grade of the Furniture can have an even greater (detrimental) impact. 

 

The link below refers to VOC's (volatile organic compounds) emitted from furniture.

http://www.ohmynews.com/NWS_Web/View/at_pg.aspx?CNTN_CD=A0002079930

 

In Korea, the law requires that all material used for furniture manufacture must be of grade E1 or higher. However, various online shopping mall advertisements state, "our furniture is eco-friendly, and uses a E1 grade material differently than other companies." (How could that be?)

 

The grade of a core material can be felt directly by the body, to the extent that if you visit any house made of "eco-friendly materials," from just the kitchen cabinets and closets, your eyes and nose will sting. 

Since the lower limit of the law is E1, if you consider your health, a core grade of E0 or higher should be used.

 

Although this matter has to do with repercussions to health, a member posted a painful experience that has direct relevance on the PHIKO association's Question and Answer Bulletin Board.

http://www.phiko.kr/bbs/board.php?bo_table=z4_04&wr_id=4005

 

 

There is not much difference in the price of the core material itself due to an increase in the grade, but the problem is that the strength of the material weakens as the grade improves resulting in a thickening of the plate to compensate, which requires a more selective pool of components for assembly that naturally raises the overall cost; on top of which, since EO is in little demand, it too is a bit more costly.

 

However, the higher price is worth it, and similar to our association's approach to our prototype houses, the top priority for furniture too, is in the Core Material Grade more than in the design. 

 

In particular, make certain to specify a grade of E0 or higher for the MDF core material used for kitchen cabinetry when placing your order. (If you ask for E0, the common response is that it is the first time they ever heard of such a request or that in their 20 years of experience E1 has been good enough.)

 

 

RECOMMENDATIONS

 

 

1. Spare Tiles

If your house is finished with brick or tiles, keep a surplus in storage. Since tiles follow trends, several months after construction is complete, if a couple of tiles are broken or need to be replaced, it is often the case that you will not be able to find the same item. Unless there is a natural disaster, 30 pieces for the exterior and 5 pieces for the interior will suffice.

 

 

2. Comparing the Relative Size of Rooms on the Floor Plan

The one thing that most distresses a Contractor during the construction process is a "change order." Of course there can be inevitable changes; however, dissatisfaction with "room size" with a request for change is the most mutually tiresome of situations.

 

In the case of the Owner, it is only after the structure is up that the actual size of the space can be felt; and when that size is unsatisfactory, after a few days of consternation when it is absolutely definite that the room size must change, a call is placed to the Contractor. The reason for waiting a few days is that the Owner knows very well that "that change is not an easy one to execute." 

 

The Owner brought up the subject with great difficulty and the Contractor who just heard this concern is blind-sided. This is when the 10 years aging process begins.

 

This matter should have been coordinated during the design phase… The architect can visualize all the room sizes; however, the layman Client cannot. This difference causes disagreements during construction.

 

It is not polite to ask for this magnitude of change after the design has been confirmed and construction has begun; nevertheless, the architect has responsibility for not imparting sufficient information beforehand.

 

The best way to prevent this type of tiresome event from happening is by including comparisons with "the room sizes you are currently living in" on the schematic design drawings.

 

For example, please refer to the drawing below.

 

It is an example of actual room sizes that the Client is currently living in drawn next to the proposed floor plan. Since the most familiar room sizes are the ones you are living in, by placing those rooms next to the proposed rooms, the layman Client is sufficiently able to gauge the proposed room sizes by comparison.

 

Or, as this too may be difficult, the most definite approach is to cut out each room that you are currently living in and place the cutouts onto the proposed floor plan drawing.

 

평면샘플.jpg 

 

Another tip is to repeat this exercise on the section drawings to get a feel for the room heights, as well as for the slope of the stairs.

 

Although there is no elevation drawing included herein, in order to get a feel for window sizes, the exercise can be repeated for elevations as well.

 

단면샘플.jpg 

  

3. Payment

The pinnacle of problems…

 

 

With regards to construction costs, the core of the problem, the main issue in today's architecture market, is the attitude that "not paying the balance or it is okay to cut the price" is somehow acceptable.

Or the advice to, "hold the balance as collateral; that is, until everything is done and repaired, do not pay in full…" 

 

The bigger problem is that this mindset is in place even before construction begins. The Contractor has an obligation to physically and psychologically complete the construction in accordance with the contract documents and the Owner has an obligation to pay for said work. This is an agreement set in stone.

 

In the event of a dispute, a thorough investigation as to the cause should be initiated; however, if there is a mindset to avoid payment before construction even begins, that project should not proceed in the first place. 

It is comparable to a Contractor thinking that, "we should induce some shoddy construction here." This type of meeting is doomed from the start.

 

"Before signing the contract, all cost cutting that is possible was done. If the Owner keeps cutting costs until final payment the Contractor will go belly-up. Who would do an honest day's work knowing it will lead to certain doom?"

 

 

Wrap-Up

It looks as though we have digressed from an explanation of Passive House.

 

 

Like the Korean "Hanok," one site orientation is ideal for a Passive House. Similarly, it may seem difficult financially or realistically for many to own either type of house right now.

 

At the beginning of this article, rather than my later digressions, I focused on the particular rumor that a Passive House costs between 10,000,000KW/py ~ 15,000,000KW/py. However, rather than debating point by point the truth or untruth about such costs, I decided that focusing on providing helpful, realistic advice to those who want to build a house economically would be a better use of this space.

 

 

Image 7

 

Also, if you can afford it, before considering a Passive House, I would recommend considering a departure from the state of the current housing market and aim for "a home-like house," or "a house free of defects."

 

If Passive Houses had ignored these prerequisites, perhaps they could have been built for as low as 4,000,000KW/py. But at the expense of delaying the mass supply of Passive  Houses, our association believes in keeping to the prerequisites.

 

 

At present, the price of Passive Houses that are designed and built by our association seems high because we have tried to keep to these principles as best as possible. But, even though we adhere to these principles, the construction cost of a Passive House is definitely not as high as the rumors purport.

 

As of yet, 5L high-performance/low energy houses that have been built in Korea have been built within 6,000,000KW/py. This price has been steadily declining and recent figures are at approximately 5,500,000KW/py. "Actual Costs" may not drop quickly; but, in the meantime, the cost of making a "home-like house" may become a reality and then we can meet somewhere in the middle. That way, the unfortunate reality of relying on Lady Luck, or leaving all to chance, will not be repeated.

---------------------------------------------------

 

I have rambled on listing things to be cautious of to all those wishing to build a house for a bargain. I welcome any other advice from our readers about their experiences to post on this Technical Note section. 

Thank-you.


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Translated by Alice J Choy (ajcblue@gmail.com)
Director of International Relations
AIA, CPHD, LEED AP+ BD+C, KIA

Comments

G 지하철 2018.01.21 17:55
다 읽지는 못했지만 훌륭~