Calculate architect's house including own contribution??

Hello everyone,

we want to build a single-family house (passive house) in the near future and are currently in the exploratory phase.
The plot of land is available and the budget has an upper limit of €300,000.

First, we looked at and compared several prefab house providers (to get a feeling for the costs). Conclusion: overwhelmed by the multitude - everyone is of course the best quality on the market.

At the same time, we are considering building the house mostly ourselves stellen/bauen or there are several carpenters and other craftsmen in our family (I am the electrician, uncle is a painter, etc.). For this reason, we went to an architect to get a rough design and cost estimate if we design and have the house built in the traditional way at the drawing board.

He sketched a rough draft and listed the house turnkey in his preliminary cost estimate
(incl. outdoor facilities, garage).
The individual trades were not explicitly calculated, instead, a base value of €350 per m³ was assumed.

Thus, the total costs amount to approx. €420,000, which exceeds the budget.
The ancillary building costs were calculated at 15% of the total sum (architect, structural engineer, surveyor, building permit, soil expert, safety coordinator).

As far as I can assess, these figures are legitimate !?! – but in our case not affordable. As already mentioned, these are the costs for a house built by external companies - but we need the total for this house if we contribute a lot of own work. So we are considering having the architect finalize the drawings or create the plans. Only then can, for example, our carpenters prepare a calculation of material costs in advance, etc. This results in a price for each trade and in the end, we have our total costs including the "family" own contribution.

If the total costs decrease accordingly, the architect’s fee would also be smaller, right?
Because the fee is always based on the previously estimated construction costs.

Now, regardless of whether we ultimately reach our targeted budget and also that we would already have to pay the planning costs for the architect (without knowing exactly whether we can then build this house due to the resulting costs):
Do I have any other chance to calculate the costs in advance in our case?

How would the experienced proceed in our case? As mentioned, we are at the very beginning and therefore perhaps somewhat naive and often thinking differently... better now than later.

Grateful for any tips....

Best regards

Hello,

we want to build a single-family house (passive house) in the foreseeable future and are currently in the discovery phase.
The plot is available and the budget has a ceiling of €300,000.

You probably mean an efficiency house 70 – a real passive house cannot be realized with this budget!

He sketched a rough draft and listed the house as turnkey in his preliminary cost estimate
(incl. outdoor facilities, garage). The individual trades were not explicitly calculated, but a base value of €350 per m³ was assumed. Thus, the total costs amount to about €420,000 and exceed the budget.
The additional construction costs were stated at 15% of the total amount (architect, structural engineer, surveyor, building permit, soil expert, SiGeKo).

I also still consider this a sporty challenge with a genuine PH as the basis. Furthermore, the lump-sum calculation carries huge risks regarding the final price. Only when receiving the individual tender documents will the final price gradually become more binding, and the numbers will be corrected step by step.

If the total costs decrease, will the architect’s fee likewise be smaller, right?
Because the fee is always based on the previously estimated construction costs.

Only marginally, since the point of construction supervision is omitted; however, a building application must be submitted. Also, the tender documents are part of the construction costs, and for the family to prepare offers, the architect must create tender documents. And finally, you need a site manager – also with tender documents – who coordinates the individual trades.

Regardless of whether we eventually reach our targeted budget and also that we would have to pay the planning costs for the architect already (without exactly knowing whether we can build this house due to the resulting costs):
Do I have any other chance to calculate the costs in advance in our case?

How would the experienced proceed in our case? As mentioned, we are at the very beginning and therefore maybe also a bit naive and often think outside the box... better now than later

The costs incurred so far are owed to the architect; these can no longer be saved. But you already have a scribble drawing.

You should first decide whether it should be a prefab or solid house. Then get offers based on the architect’s scribble drawing – absolutely comparable offers – and you will have an approximate benchmark for what your new home will ultimately cost.

Rhenish greetings

Hello,

and thank you for the quick response.

Hello,
You probably mean an Efficiency House 70 - a real PH cannot be realized with this budget!

The goal was definitely a Passive House - the Passive House surcharge in the architect’s rough cost calculation is 7% of the construction costs, so about €20,000.

I still consider that a sporty challenge, assuming a real PH. Furthermore, the flat-rate calculation carries huge risks regarding the final price. Only when the individual bill of quantities (BOQ) becomes available does the final price become increasingly binding and the figures are gradually adjusted.

That’s exactly what I meant, or rather we would never start our construction project based on a flat-rate calculation. Therefore, precise specifications or BOQ are necessary—so the family can prepare quotes and thus the final price can be calculated step by step. Hopefully, our budget will suffice. So far, the architect hasn’t cost us anything—it was just a first proposal based on a handwritten design sketch and a cost estimate.

In order for the architect to prepare the BOQ now, the detailed planning of the house must actually be completely finished—every single trade. And this, above all, time-consuming planning of our house is not something the architect will necessarily want to do for free.
So first we have to invest money in the planning so that the architect can ultimately put the BOQ out to tender and we can see whether we can ultimately afford the construction project. If we cannot afford it, the planning costs have objectively been wasted. It’s not like a prefabricated house, where I can get a price for the ready-made house relatively quickly; rather, I have to pay for the architect’s planning so it becomes clear exactly how much the project will cost us. Or did I misunderstand something?

Only marginally, since the construction supervision point is omitted; however, a building application must be submitted. The specifications (EL) are also part of the construction costs and therefore, so that the family can obtain offers, the architect must prepare BOQ. And ultimately, even with EL, you need a construction manager who coordinates the individual trades.

The point of construction supervision should not be omitted; I want our construction project to be overseen by the architect. What I don’t quite understand: assuming the previously roughly estimated final price decreases after the tender due to the owner’s share. Then the incidental construction costs and the architect’s fee would also decrease, since the latter is based on the total construction costs, right?

You should first decide whether it will be a prefab or a solid house. Then get comparable quotes based on the architect’s sketch drawing, and you will have an approximate benchmark of what your new home will ultimately cost.

It should definitely be a timber frame house. Then I’m curious whether the carpentry will be able to provide me with a cost estimate based on the sketch drawing. Basically, at the moment, I can only provide them with the approximate m² per floor and a floor plan.

thx...best regards!

Hello,

The goal was definitely a passive house - the passive house surcharge in the architect's rough cost calculation is 7% of the house construction costs, so about €20,000.

No way. A passive house is a building in which a comfortable temperature can be achieved both in winter and in summer without a separate heating or air conditioning system. It offers increased living comfort with a heating demand of less than 15 kWh/(m²a) and a primary energy demand including hot water and household electricity of under 120 kWh/(m²a). In my opinion - even with a timber frame construction in the range of €20,000 - this is not feasible, even though I originally come from solid construction; the required windows alone cost a small fortune.

Or did I misunderstand something?

No, you understood that correctly.

What I don’t quite understand: Suppose the roughly estimated final price so far becomes smaller after the tender due to the owner’s contribution. Then the ancillary construction costs and the architect’s fee decrease as well, since the latter is based on the total construction costs, right?

No - the calculation of the pure construction costs includes the owner’s contribution, because without the owner’s contribution the house could not be completed. Therefore, the total construction costs - including the owner’s contribution - are the basis for calculating the architect’s fee.

Rhenish regards

Hello,

thank you for the explanation. It makes sense to me that the construction costs including EL are the basis for calculating the architect’s fee. Nevertheless, I have to play the slow learner once more – example: Suppose the architect estimates the house to be built at €300,000 in his preliminary cost estimate. The client is enthusiastic and wants to realize the construction project – the architect sits down at the drawing board and creates the plans, then the individual trades are tendered and the respective companies submit their offers. From these offers (EL completely disregarded for the moment) the total and actual construction costs ultimately arise, and these now amount to €250,000 (inexpensive craftsmen ). Which amount now serves as the basis for the architect’s fee: the €300,000 from the preliminary estimate or the €250,000 (total construction costs)??

Hello,
No way. A passive house is a building in which a comfortable temperature can be achieved both in winter and in summer without a separate heating or air conditioning system. It offers increased living comfort with a heating energy demand of less than 15 kWh/(m²a) and a primary energy demand including hot water and household electricity of under 120 kWh/(m²a). In my opinion – even with timber frame construction in the TEUR 20 range, this cannot be realized – even though I originally come from solid construction; the required windows alone cost a small fortune.

so, not to be misunderstood – the €20,000 is the surcharge to achieve the passive house standard for the offered property, basically energy-efficient base construction + 7% = passive house. That’s how I interpret it, and the architect has already built many passive houses and is also mentioned in the Passive House Compendium 2013 (the category was something like best/most beautiful passive houses). So it should actually fit accordingly in my opinion....

Winter greetings!

Hello,

Still have to play the slow learner once more - example: Suppose the architect estimates the house to be built at €300,000 in his preliminary cost estimation. The client is thrilled and wants to realize the construction project - the architect sits down at the drawing board and creates the plans, then the individual trades are tendered and the respective companies submit their bids. From these bids (completely disregarding EL for now), the total actual construction costs ultimately arise, and these now amount to €250,000 (inexpensive craftsmen ). Which amount now serves as the basis for the architect’s fee: the €300,000 from the preliminary estimate or the €250,000 (total construction costs)??

I’d hate to disappoint you ... only, in my opinion that won’t happen

But never mind: You conclude a contract with your architect for work phases x to y. In this contract, you can additionally lay down everything that is important to you in writing – provided the architect plays along ... including the question of the fee in relation to the initial cost estimate versus possibly lower construction costs after submission of all tenders. What remains unchangeable, however, is the HOAI, which is always the basis.

.... quasi energy-efficient basic execution + 7% = Passive House ...

What does "energy-efficient basic execution" mean?

Best regards from the Rhineland