5 person johkasou supplier in Bangladesh

Roptan is a 5 person johkasou supplier in Bangladesh for households that want one contact. Tell us who lives in the house and where the outlet goes: we source a unit from a verified seller, check its papers and deliver it.

Verified sellers
Checked before it ships
Delivered by Roptan

Prefer to deal with suppliers yourself? Post it on the requirement board

Buying 5 person johkasou in Bangladesh

A 5 person johkasou is the household size of the Japanese buried treatment tank. It takes toilet, kitchen and bath water, treats it in anaerobic and aerated chambers, settles it and disinfects it. Japan sizes units in person equivalents: one is 200 litres of wastewater and 40 g of BOD a day. In Bangladesh this size suits family houses and villas with no sewer.

A 5 person johkasou supplier in Bangladesh should start from your household, not a catalogue. Roptan sources from verified sellers, asks for the sizing calculation and the model's papers, and compares installed prices with the site work included. The seller or its installer sets and starts the unit; we agree the service plan before handover.

Kinds of 5 person johkasou

Standard contact aeration units

The classic Japanese layout: two anaerobic chambers, an aerated chamber, settling and disinfection. Japan's reference 5 person model treats 1 m³ a day in a tank of about 3 m³. Choose it where the plot has room.

Compact certified units

Designs certified on performance, not built to the standard layout. In Japan the compact class for 5 persons is under 1.5 m³. Choose it for a tight plot, and ask how much sludge it stores.

Nitrogen removal units

Certified in Japan to under 10 mg/L of BOD and of total nitrogen; a further class adds phosphorus under 1 mg/L. Choose one where treated water reaches a pond or canal near the house.

Membrane separation units

Treated water passes a membrane filter, and the Japanese class is under 5 mg/L of BOD. Choose it when the outlet must be very clear, and ask what membrane care the service plan covers.

How to brief a 5 person johkasou supplier in Bangladesh

People on the busiest day: Count residents, live-in staff and regular guests. A 5 person unit is designed for 1,000 litres and 200 g of BOD a day, so a fuller house overloads it.
Floor area and kitchens: Japan's sizing table typically counts a house up to 130 m² as 5 persons, a larger one as 7, and one with two kitchens and two bathrooms as 10.
What flows in: Toilet, kitchen and bath water only. Keep rainwater, cooking oil, nappies, sanitary goods and pesticides out; a heavy kitchen needs a grease trap first.
Groundwater and access: Give the highest monsoon water level: wet ground means dewatering and holding the tank down. Keep the lids clear and reachable by the desludging tanker.
Blower power: The blower stands on its own base with an earthed, waterproof supply, usually single phase, 50 Hz. Wire it to the circuit that stays live through load shedding.
Outlet: Say where treated water goes, drain, canal or soak pit, and give its level.

Laws, standards and papers to ask about

Johkasou Act (Japan): Act No. 43 of 1983 governs installation, upkeep, desludging and manufacture in Japan. It is not a Bangladesh rule, but its duties make a useful model for a service contract.
Structure type and approval: Japanese law recognises standard and performance-certified structures, and approves factory-made types for 5 years. Ask which applies, and for the approval document or a statement that there is none.
JIS A 3302: The Japanese Industrial Standard for estimating how many persons a johkasou serves from the building's use. Ask the seller to show the calculation for your house.
ECR 2023: The Environment Conservation Rules 2023 hold Bangladesh's effluent discharge standards. Ask for the expected outlet BOD and TSS in writing, and a lab test once treatment settles.

What moves the price of a 5 person johkasou

Process class: a standard unit usually costs less than a nitrogen removal or membrane design of the same size.
Tank design: a compact certified tank needs a smaller pit.
Ground: dewatering and holding the tank down add civil work on wet sites.
Civil work: rubble bed, base plate and top slab, often quoted apart from the tank.
Upkeep: chlorine tablets, blower servicing, inspections and yearly desludging, per visit or by contract.

Lead times and delivery

Timing depends on whether the seller holds the model in Bangladesh or brings it in to order, and on the ground. Monsoon groundwater slows the dig, and the base plate and top slab are cast on site. The outlet is tested only once treatment has settled. Roptan confirms delivery and installation dates, and any minimum, in the quote.

We deliver to your site across Bangladesh. The seller or its installer lays a rubble bed, levelling concrete and a reinforced base plate, sets the tank level and fills it with water before backfilling in layers. Pipes and blower are connected, the top slab is cast and the unit is test run. Handover brings the documents, an upkeep briefing and a VAT invoice (Mushak 6.3).

What we check for this order

Sizing in person equivalentsWe check the seller's calculation against your household on its busiest day.
Structure type and papersWe confirm in writing the structure type and whether a Japanese type approval exists.
Base and level before backfillWe ask for photos of the base plate, level tank and any hold-down before backfill.
Test run at handoverWe check the record that the blower runs, water flows through each chamber and tablets are loaded.

Questions buyers ask

Is a 5 person johkasou enough for my house?

Usually, for one household of up to five people. Japan's table typically moves a house above 130 m² to 7 persons, and two kitchens with two bathrooms to 10. Fractions are rounded up, so if your count falls between sizes, choose the next one.

How often does it need desludging?

Once a year under Japanese rules, more often where use or sludge storage calls for it. The maker should state the sludge storage capacity and when to desludge. We found no matching Bangladesh duty, so put the interval in the service contract.

Can I switch the blower off at night to save power?

No. Japan's maintenance rules say never to turn the blower off: the aerated chamber must keep its dissolved oxygen up day and night, with no dead zone, and only a running blower does that. Put the blower on the circuit that stays live during load shedding, such as the IPS or generator.

Is a johkasou required by law in Bangladesh?

Not under the Johkasou Act, which is Japanese law. Treated water discharged in Bangladesh falls under the effluent standards of the Environment Conservation Rules 2023, so ask the seller to state the outlet quality the unit should reach.

How soon will I hear back about johkasou?

Within 48 hours of a complete requirement, with a price and a delivery date. A requirement is complete when it has the capacity, where it is needed and by when.

Who do I deal with?

With Roptan, when Roptan manages the order: we buy from the verified seller and deliver to you. With the supplier directly, when you post on the requirement board and choose a quote yourself.